Publications


Search for neutrino-induced particle showers with IceCube-40

ArXiv (2013)

I Collaboration, MG Aartsen, R Abbasi, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, C Arguelles, TC Arlen, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, JB Tjus, KH Becker, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, L Classen, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, M Day, JPAMD André, CD Clercq, SD Ridder, P Desiati, KDD Vries, MD With, T DeYoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, B Eichmann, J Eisch, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, DT Grandmont, D Grant, P Gretskov, JC Groh, A Groß, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Hebecker, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, F Huang, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, M Kauer, JL Kelley, J Kiryluk, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, A Kriesten, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, O Macías, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, A Omairat, A O'Murchadha, T Palczewski, L Paul, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, M Quinnan, L Rädel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, S Robertson, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, HG Sander, M Santander, S Sarkar, K Schatto, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, R Shanidze, C Sheremata, MWE Smith, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, NA Stanisha, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, NL Strotjohann, GW Sullivan, H Taavola, I Taboada, A Tamburro, A Tepe, S Ter-Antonyan, G Tešić, S Tilav, PA Toale, MN Tobin, S Toscano, M Tselengidou, E Unger, M Usner, S Vallecorsa, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, C Weaver, M Wellons, C Wendt, S Westerhoff, B Whelan, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, M Zoll

We report on the search for neutrino-induced particle-showers, so-called cascades, in the IceCube-40 detector. The data for this search was collected between April 2008 and May 2009 when the first 40 IceCube strings were deployed and operational. Three complementary searches were performed, each optimized for different energy regimes. The analysis with the lowest energy threshold (2 TeV) targeted atmospheric neutrinos. A total of 67 events were found, consistent with the expectation of 41 atmospheric muons and 30 atmospheric neutrino events. The two other analyses targeted a harder, astrophysical neutrino flux. The analysis with an intermediate threshold of 25 TeV lead to the observation of 14 cascade-like events, again consistent with the prediction of 3.0 atmospheric neutrino and 7.7 atmospheric muon events. We hence set an upper limit of $E^2 \Phi_{lim} \leq 7.46\times10^{-8}\,\mathrm{GeV sr^{-1} s^{-1} cm^{-2}}$ (90% C.L.) on the diffuse flux from astrophysical neutrinos of all neutrino flavors, applicable to the energy range 25 TeV to 5 PeV, assuming an $E_{\nu}^{-2}$ spectrum and a neutrino flavor ratio of 1:1:1 at the Earth. The third analysis utilized a larger and optimized sample of atmospheric muon background simulation, leading to a higher energy threshold of 100 TeV. Three events were found over a background prediction of 0.04 atmospheric muon events and 0.21 events from the flux of conventional and prompt atmospheric neutrinos. Including systematic errors this corresponds to a $2.7\sigma$ excess with respect to the background-only hypothesis. Our observation of neutrino event candidates above 100 TeV complements IceCube's recently observed evidence for high-energy astrophysical neutrinos.


Measurement of Atmospheric Neutrino Oscillations with IceCube

ArXiv (2013)

TI Collaboration

We present the first statistically significant detection of neutrino oscillations in the high-energy regime ($>$ 20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010-2011. This measurement is made possible by the low energy threshold of the DeepCore detector ($\sim 20$ GeV) and benefits from the use of the IceCube detector as a veto against cosmic ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20 -- 100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV -- 10 TeV) was extracted from IceCube data to constrain systematic uncertainties. Disappearance of low-energy upward-going muon neutrinos was observed, and the non-oscillation hypothesis is rejected with more than $5\sigma$ significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters $\Delta m^2_{23}= (2.3^{+0.6}_{-0.5})\cdot 10^{-3}$ eV$^2$ and $\sin^2(2 \theta_{23})>0.93$, and maximum mixing is favored.


Linear structures in the core of the Coma cluster of galaxies

Science 341 (2013) 1365-1368

JS Sanders, AC Fabian, E Churazov, AA Schekochihin, A Simionescu, SA Walker, N Werner

The hot x-ray-emitting plasma in galaxy clusters is predicted to have turbulent motion, which can contribute around 10% of the cluster's central energy density. We report deep Chandra X-ray Observatory observations of the Coma cluster core, showing the presence of quasi-linear high-density arms spanning 150 kiloparsecs, consisting of low-entropy material that was probably stripped from merging subclusters. Two appear to be connected with a subgroup of galaxies at a 650-kiloparsec radius that is merging into the cluster, implying coherence over several hundred million years. Such a long lifetime implies that strong isotropic turbulence and conduction are suppressed in the core, despite the unrelaxed state of the cluster. Magnetic fields are presumably responsible. The structures seen in Coma present insight into the past billion years of subcluster merger activity.


The unbearable lightness of being: CDMS versus XENON

ArXiv (2013)

MT Frandsen, F Kahlhoefer, C McCabe, S Sarkar, K Schmidt-Hoberg

The CDMS-II collaboration has reported 3 events in a Si detector, which are consistent with being nuclear recoils due to scattering of Galactic dark matter particles with a mass of about 8.6 GeV and a cross-section on neutrons of about 2 x 10^-41 cm^2. While a previous result from the XENON10 experiment has supposedly ruled out such particles as dark matter, we find by reanalysing the XENON10 data that this is not the case. Some tension remains however with the upper limit placed by the XENON100 experiment, independently of astrophysical uncertainties concerning the Galactic dark matter distribution. We explore possible ways of ameliorating this tension by altering the properties of dark matter interactions. Nevertheless, even with standard couplings, light dark matter is consistent with both CDMS and XENON10/100.


Overview of physics results from MAST towards ITER/DEMO and the MAST Upgrade

Nuclear Fusion 53 (2013)

H Meyer, IG Abel, RJ Akers, A Allan, SY Allan, LC Appel, O Asunta, M Barnes, NC Barratt, N Ben Ayed, JW Bradley, J Canik, P Cahyna, M Cecconello, CD Challis, IT Chapman, D Ciric, G Colyer, NJ Conway, M Cox, BJ Crowley, SC Cowley, G Cunningham, A Danilov, A Darke, MFM De Bock, G De Temmerman, RO Dendy, P Denner, D Dickinson, AY Dnestrovsky, Y Dnestrovsky, MD Driscoll, B Dudson, D Dunai, M Dunstan, P Dura, S Elmore, AR Field, G Fishpool, S Freethy, W Fundamenski, L Garzotti, YC Ghim, KJ Gibson, MP Gryaznevich, J Harrison, E Havlíčková, NC Hawkes, WW Heidbrink, TC Hender, E Highcock, D Higgins, P Hill, B Hnat, MJ Hole, J Horáček, DF Howell, K Imada, O Jones, E Kaveeva, D Keeling, A Kirk, M Kočan, RJ Lake, M Lehnen, HJ Leggate, Y Liang, MK Lilley, SW Lisgo, YQ Liu, B Lloyd, GP Maddison, J Mailloux, R Martin, GJ McArdle, KG McClements, B McMillan, C Michael, F Militello, P Molchanov, S Mordijck, T Morgan, AW Morris, DG Muir, E Nardon, V Naulin, G Naylor, AH Nielsen, MR O'Brien, T O'Gorman, S Pamela, FI Parra, A Patel, SD Pinches, MN Price, CM Roach, JR Robinson, M Romanelli, V Rozhansky, S Saarelma, S Sangaroon, A Saveliev, R Scannell, J Seidl, SE Sharapov, AA Schekochihin, V Shevchenko, S Shibaev, D Stork, J Storrs, A Sykes, GJ Tallents, P Tamain, D Taylor, D Temple, N Thomas-Davies, A Thornton, MR Turnyanskiy, M Valovič, RGL Vann, E Verwichte, P Voskoboynikov, G Voss, SEV Warder, HR Wilson, I Wodniak, S Zoletnik, R Zagôrski

New diagnostic, modelling and plant capability on the Mega Ampère Spherical Tokamak (MAST) have delivered important results in key areas for ITER/DEMO and the upcoming MAST Upgrade, a step towards future ST devices on the path to fusion currently under procurement. Micro-stability analysis of the pedestal highlights the potential roles of micro-tearing modes and kinetic ballooning modes for the pedestal formation. Mitigation of edge localized modes (ELM) using resonant magnetic perturbation has been demonstrated for toroidal mode numbers n = 3, 4, 6 with an ELM frequency increase by up to a factor of 9, compatible with pellet fuelling. The peak heat flux of mitigated and natural ELMs follows the same linear trend with ELM energy loss and the first ELM-resolved Ti measurements in the divertor region are shown. Measurements of flow shear and turbulence dynamics during L-H transitions show filaments erupting from the plasma edge whilst the full flow shear is still present. Off-axis neutral beam injection helps to strongly reduce the redistribution of fast-ions due to fishbone modes when compared to on-axis injection. Low-k ion-scale turbulence has been measured in L-mode and compared to global gyro-kinetic simulations. A statistical analysis of principal turbulence time scales shows them to be of comparable magnitude and reasonably correlated with turbulence decorrelation time. Te inside the island of a neoclassical tearing mode allow the analysis of the island evolution without assuming specific models for the heat flux. Other results include the discrepancy of the current profile evolution during the current ramp-up with solutions of the poloidal field diffusion equation, studies of the anomalous Doppler resonance compressional Alfvén eigenmodes, disruption mitigation studies and modelling of the new divertor design for MAST Upgrade. The novel 3D electron Bernstein synthetic imaging shows promising first data sensitive to the edge current profile and flows. © 2013 IAEA, Vienna.


The IceCube Neutrino Observatory Part V: Neutrino Oscillations and Supernova Searches

ArXiv (2013)

I Collaboration, MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, JB Tjus, KH Becker, M Bell, ML Benabderrahmane, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, CD Clercq, SD Ridder, P Desiati, KDD Vries, MD With, T DeYoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, DT Grandmont, D Grant, A Groß, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, JL Kelley, J Kiryluk, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, M Olivo, A O'Murchadha, L Paul, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, L Rädel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, R Shanidze, C Sheremata, MWE Smith, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, GW Sullivan, H Taavola, I Taboada, A Tamburro, A Tepe, S Ter-Antonyan, G Tešić, S Tilav, PA Toale, S Toscano, M Usner, DVD Drift, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, R Wasserman, C Weaver, M Wellons, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, M Zoll

Papers on neutrino oscillation and supernova searches submitted to the 33nd International Cosmic Ray Conference (Rio de Janeiro 2013) by the IceCube Collaboration.


First observation of PeV-energy neutrinos with IceCube

ArXiv (2013)

I Collaboration, MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, JB Tjus, KH Becker, M Bell, ML Benabderrahmane, S BenZvi, J Berdermann, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, CD Clercq, SD Ridder, P Desiati, MD With, T DeYoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, R Franke, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, D Grant, A Groß, M Gurtner, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, JL Kelley, J Kiryluk, F Kislat, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, J Madsen, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, M Olivo, A O'Murchadha, L Paul, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, N Pirk, J Posselt, PB Price, GT Przybylski, L Rädel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, C Sheremata, MWE Smith, M Soiron, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, GW Sullivan, H Taavola, I Taboada, A Tamburro, S Ter-Antonyan, G Tešić, S Tilav, PA Toale, S Toscano, M Usner, DVD Drift, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, R Wasserman, C Weaver, M Wellons, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, C Xu, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, A Zilles, M Zoll

We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04 $\pm$ 0.16 and 1.14 $\pm$ 0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current $\nu_{e,\mu,\tau}$ ($\bar\nu_{e,\mu,\tau}$) or charged-current $\nu_{e}$ ($\bar\nu_{e}$) interactions within the IceCube detector. The events were discovered in a search for ultra-high energy neutrinos using data corresponding to 615.9 days effective livetime. The expected number of atmospheric background is $0.082 \pm 0.004 \text{(stat)}^{+0.041}_{-0.057} \text{(syst)}$. The probability to observe two or more candidate events under the atmospheric background-only hypothesis is $2.9\times10^{-3}$ ($2.8\sigma$) taking into account the uncertainty on the expected number of background events. These two events could be a first indication of an astrophysical neutrino flux, the moderate significance, however, does not permit a definitive conclusion at this time.


CONSTRAINTS ON THE ORIGIN OF COSMIC RAYS ABOVE 10(18) eV FROM LARGE-SCALE ANISOTROPY SEARCHES IN DATA OF THE PIERRE AUGER OBSERVATORY

ASTROPHYSICAL JOURNAL LETTERS 762 (2013) ARTN L13

P Abreu, M Aglietta, M Ahlers, EJ Ahn, IFM Albuquerque, D Allard, I Allekotte, J Allen, P Allison, A Almela, J Alvarez Castillo, J Alvarez-Muniz, R Alves Batista, M Ambrosio, A Aminaei, L Anchordoqui, S Andringa, T Antici'c, C Aramo, E Arganda, F Arqueros, H Asorey, P Assis, J Aublin, M Ave, M Avenier, G Avila, AM Badescu, M Balzer, KB Barber, AF Barbosa, R Bardenet, SLC Barroso, B Baughman, J Baeuml, C Baus, JJ Beatty, KH Becker, A Belletoile, JA Bellido, S BenZvi, C Berat, X Bertou, PL Biermann, P Billoir, F Blanco, M Blanco, C Bleve, H Bluemer, M Bohacova, D Boncioli, C Bonifazi, R Bonino, N Borodai, J Brack, I Brancus, P Brogueira, WC Brown, R Bruijn, P Buchholz, A Bueno, L Buroker, RE Burton, KS Caballero-Mora, B Caccianiga, L Caramete, R Caruso, A Castellina, O Catalano, G Cataldi, L Cazon, R Cester, J Chauvin, SH Cheng, A Chiavassa, JA Chinellato, J Chirinos Diaz, J Chudoba, M Cilmo, RW Clay, G Cocciolo, L Collica, MR Coluccia, R Conceicao, F Contreras, H Cook, MJ Cooper, J Coppens, A Cordier, S Coutu, CE Covault, A Creusot, A Criss, J Cronin, A Curutiu, S Dagoret-Campagne, R Dallier, B Daniel, S Dasso, K Daumiller, BR Dawson, RM de Almeida, M De Domenico, C De Donato, SJ de Jong, G De La Vega, DMWJM Jr, JRT de Mello Neto, I De Mitri, V de Souza, KD de Vries, L del Peral, M del Rio, O Deligny, H Dembinski, N Dhital, C Di Giulio, ML Diaz Castro, PN Diep, F Diogo, C Dobrigkeit, W Docters, JC D'Olivo, PN Dong, A Dorofeev, JC dos Anjos, MT Dova, D D'Urso, I Dutan, J Ebr, R Engel, M Erdmann, CO Escobar, J Espadanal, A Etchegoyen, P Facal San Luis, H Falcke, K Fang, G Farrar, AC Fauth, N Fazzini, AP Ferguson, B Fick, JM Figueira, A Filevich, A Filipcic, S Fliescher, CE Fracchiolla, ED Fraenkel, O Fratu, U Froehlich, B Fuchs, R Gaior, RF Gamarra, S Gambetta, B Garcia, ST Garcia Roca, D Garcia-Gamez, D Garcia-Pinto, G Garilli, A Gascon Bravo, H Gemmeke, PL Ghia, M Giller, J Gitto, H Glass, MS Gold, G Golup, F Gomez Albarracin, M Gomez Berisso, PF Gomez Vitale, P Goncalves, JG Gonzalez, B Gookin, A Gorgi, P Gouffon, E Grashorn, S Grebe, N Griffith, AF Grillo, Y Guardincerri, F Guarino, GP Guedes, P Hansen, D Harari, TA Harrison, JL Harton, A Haungs, T Hebbeker, D Heck, AE Herve, GC Hill, C Hojvat, N Hollon, VC Holmes, P Homola, JR Hoerandel, P Horvath, M Hrabovsky, D Huber, T Huege, A Insolia, F Ionita, A Italiano, S Jansen, C Jarne, S Jiraskova, M Josebachuili, K Kadija, KH Kampert, P Karhan, P Kasper, I Katkov, B Kegl, B Keilhauer, A Keivani, JL Kelley, E Kemp, RM Kieckhafer, HO Klages, M Kleifges, J Kleinfeller, J Knapp, D-H Koang, K Kotera, N Krohm, O Kroemer, D Kruppke-Hansen, D Kuempel, JK Kulbartz, N Kunka, G La Rosa, C Lachaud, D LaHurd, L Latronico, R Lauer, P Lautridou, S Le Coz, MSAB Leao, D Lebrun, P Lebrun, MA Leigui de Oliveira, A Letessier-Selvon, I Lhenry-Yvon, K Link, R Lopez, A Lopez Agueera, K Louedec, J Lozano Bahilo, L Lu, A Lucero, M Ludwig, H Lyberis, MC Maccarone, C Macolino, S Maldera, J Maller, D Mandat, P Mantsch, AG Mariazzi, J Marin, V Marin, IC Maris, HR Marquez Falcon, G Marsella, D Martello, L Martin, H Martinez, O Martinez Bravo, D Martraire, JJ Masias Meza, HJ Mathes, J Matthews, JAJ Matthews, G Matthiae, D Maurel, D Maurizio, PO Mazur, G Medina-Tanco, M Melissas, D Melo, E Menichetti, A Menshikov, P Mertsch, S Messina, C Meurer, R Meyhandan, S Mi'canovi'c, MI Micheletti, IA Minaya, L Miramonti, L Molina-Bueno, S Mollerach, M Monasor, D Monnier Ragaigne, F Montanet, B Morales, C Morello, E Moreno, JC Moreno, M Mostafa, CA Moura, MA Muller, G Mueller, M Muenchmeyer, R Mussa, G Navarra, JL Navarro, S Navas, P Necesal, L Nellen, A Nelles, J Neuser, PT Nhung, M Niechciol, L Niemietz, N Nierstenhoefer, D Nitz, D Nosek, L Nozka, J Oehlschlaeger, A Olinto, M Ortiz, N Pacheco, DP Selmi-Dei, M Palatka, J Pallotta, N Palmieri, G Parente, E Parizot, A Parra, S Pastor, T Paul, M Pech, J Pekala, R Pelayo, IM Pepe, L Perrone, R Pesce, E Petermann, S Petrera, A Petrolini, Y Petrov, C Pfendner, R Piegaia, T Pierog, P Pieroni, M Pimenta, V Pirronello, M Platino, M Plum, VH Ponce, M Pontz, A Porcelli, P Privitera, M Prouza, EJ Quel, S Querchfeld, J Rautenberg, O Ravel, D Ravignani, B Revenu, J Ridky, S Riggi, M Risse, P Ristori, H Rivera, V Rizi, J Roberts, W Rodrigues de Carvalho, G Rodriguez, I Rodriguez Cabo, J Rodriguez Martino, J Rodriguez Rojo, MD Rodriguez-Frias, G Ros, J Rosado, T Rossler, M Roth, B Rouille-d'Orfeuil, E Roulet, AC Rovero, C Ruehle, A Saftoiu, F Salamida, H Salazar, F Salesa Greus, G Salina, F Sanchez, CE Santo, E Santos, EM Santos, F Sarazin, B Sarkar, S Sarkar, R Sato, N Scharf, V Scherini, H Schieler, P Schiffer, A Schmidt, O Scholten, H Schoorlemmer, J Schovancova, P Schovanek, F Schroeder, D Schuster, SJ Sciutto, M Scuderi, A Segreto, M Settimo, A Shadkam, RC Shellard, I Sidelnik, G Sigl, HH Silva Lopez, O Sima, A 'Smiallkowski, R Smida, GR Snow, P Sommers, J Sorokin, H Spinka, R Squartini, YN Srivastava, S Stanic, J Stapleton, J Stasielak, M Stephan, A Stutz, F Suarez, T Suomijaervi, AD Supanitsky, T Susa, MS Sutherland, J Swain, Z Szadkowski, M Szuba, A Tapia, M Tartare, O Tascau, R Tcaciuc, NT Thao, D Thomas, J Tiffenberg, C Timmermans, W Tkaczyk, CJ Todero Peixoto, G Toma, L Tomankova, B Tome, A Tonachini, G Torralba Elipe, P Travnicek, DB Tridapalli, G Tristram, E Trovato, M Tueros, R Ulrich, M Unger, M Urban, JF Valdes Galicia, I Valino, L Valore, G van Aar, AM van den Berg, S van Velzen, A van Vliet, E Varela, B Vargas Cardenas, JR Vazquez, RA Vazquez, D Veberic, V Verzi, J Vicha, M Videla, L Villasenor, H Wahlberg, P Wahrlich, O Wainberg, D Walz, AA Watson, M Weber, K Weidenhaupt, A Weindl, F Werner, S Westerhoff, BJ Whelan, A Widom, G Wieczorek, L Wiencke, B Wilczynska, H Wilczynski, M Will, C Williams, T Winchen, M Wommer, B Wundheiler, T Yamamoto, T Yapici, P Younk, G Yuan, A Yushkov, B Zamorano Garcia, E Zas, D Zavrtanik, M Zavrtanik, I Zaw, A Zepeda, J Zhou, Y Zhu, M Zimbres Silva, M Ziolkowski, PA Collaboration


The IceCube Neutrino Observatory Part VI: Ice Properties, Reconstruction and Future Developments

ArXiv (2013)

I Collaboration, MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, JB Tjus, KH Becker, M Bell, ML Benabderrahmane, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, CD Clercq, SD Ridder, P Desiati, KDD Vries, MD With, T DeYoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, DT Grandmont, D Grant, A Groß, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, JL Kelley, J Kiryluk, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, M Olivo, A O'Murchadha, L Paul, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, L Rädel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, R Shanidze, C Sheremata, MWE Smith, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, GW Sullivan, H Taavola, I Taboada, A Tamburro, A Tepe, S Ter-Antonyan, G Tešić, S Tilav, PA Toale, S Toscano, M Usner, DVD Drift, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, R Wasserman, C Weaver, M Wellons, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, M Zoll

Papers on ice properties, reconstruction and future developments submitted to the 33nd International Cosmic Ray Conference (Rio de Janeiro 2013) by the IceCube Collaboration.


Plasmoid and Kelvin-Helmholtz instabilities in Sweet-Parker current sheets

ArXiv (2012)

NF Loureiro, AA Schekochihin, DA Uzdensky

A 2D linear theory of the instability of Sweet-Parker (SP) current sheets is developed in the framework of Reduced MHD. A local analysis is performed taking into account the dependence of a generic equilibrium profile on the outflow coordinate. The plasmoid instability [Loureiro et al, Phys. Plasmas {\bf 14}, 100703 (2007)] is recovered, i.e., current sheets are unstable to the formation of a large-wave-number chain of plasmoids ($k_{\rm max}\Lsheet \sim S^{3/8}$, where $k_{\rm max}$ is the wave-number of fastest growing mode, $S=\Lsheet V_A/\eta$ is the Lundquist number, $\Lsheet$ is the length of the sheet, $V_A$ is the Alfv\'en speed and $\eta$ is the plasma resistivity), which grows super-Alfv\'enically fast ($\gmax\tau_A\sim S^{1/4}$, where $\gmax$ is the maximum growth rate, and $\tau_A=\Lsheet/V_A$). For typical background profiles, the growth rate and the wave-number are found to {\it increase} in the outflow direction. This is due to the presence of another mode, the Kelvin-Helmholtz (KH) instability, which is triggered at the periphery of the layer, where the outflow velocity exceeds the Alfv\'en speed associated with the upstream magnetic field. The KH instability grows even faster than the plasmoid instability, $\gmax \tau_A \sim k_{\rm max} \Lsheet\sim S^{1/2}$. The effect of viscosity ($\nu$) on the plasmoid instability is also addressed. In the limit of large magnetic Prandtl numbers, $Pm=\nu/\eta$, it is found that $\gmax\sim S^{1/4}Pm^{-5/8}$ and $k_{\rm max} \Lsheet\sim S^{3/8}Pm^{-3/16}$, leading to the prediction that the critical Lundquist number for plasmoid instability in the $Pm\gg1$ regime is $\Scrit\sim 10^4Pm^{1/2}$. These results are verified via direct numerical simulation of the linearized equations, using a new, analytical 2D SP equilibrium solution.


The IceCube Neutrino Observatory Part IV: Searches for Dark Matter and Exotic Particles

ArXiv (2013)

I Collaboration, MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, JB Tjus, KH Becker, M Bell, ML Benabderrahmane, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, CD Clercq, SD Ridder, P Desiati, KDD Vries, MD With, T DeYoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, DT Grandmont, D Grant, A Groß, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, JL Kelley, J Kiryluk, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, M Olivo, A O'Murchadha, L Paul, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, L Rädel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, R Shanidze, C Sheremata, MWE Smith, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, GW Sullivan, H Taavola, I Taboada, A Tamburro, A Tepe, S Ter-Antonyan, G Tešić, S Tilav, PA Toale, S Toscano, M Usner, DVD Drift, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, R Wasserman, C Weaver, M Wellons, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, M Zoll

Papers on searches for Dark Matter and exotic particles submitted to the 33nd International Cosmic Ray Conference (Rio de Janeiro 2013) by the IceCube Collaboration.


High Mach-number collisionless shock driven by a laser with an external magnetic field

EPJ Web of Conferences 59 (2013)

T Morita, Y Sakawa, Y Kuramitsu, T Ide, K Nishio, M Kuwada, H Ide, K Tsubouchi, H Yoneda, A Nishida, T Namiki, T Norimatsu, K Tomita, K Nakayama, K Inoue, K Uchino, M Nakatsutsumi, A Pelka, M Koenig, Q Dong, D Yuan, G Gregori, H Takabe

Collisionless shocks are produced in counter-streaming plasmas with an external magnetic field. The shocks are generated due to an electrostatic field generated in counter-streaming laser-irradiated plasmas, as reported previously in a series of experiments without an external magnetic field [T. Morita et al., Phys. Plasmas, 17, 122702 (2010), Kuramitsu et al., Phys. Rev. Lett., 106, 175002 (2011)] via laser-irradiation of a double-CH-foil target. A magnetic field is applied to the region between two foils by putting an electro-magnet (∼10 T) perpendicular to the direction of plasma expansion. The generated shocks show different characteristics later in time (t > 20ns). © Owned by the authors, published by EDP Sciences, 2013.


Searches for high-energy neutrino emission in the Galaxy with the combined IceCube-AMANDA detector

ArXiv (2012)

I collaboration, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, K Andeen, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, K Beattie, JJ Beatty, S Bechet, JB Tjus, KH Becker, M Bell, ML Benabderrahmane, S BenZvi, J Berdermann, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, C Bohm, D Bose, S Böser, O Botner, L Brayeur, AM Brown, R Bruijn, J Brunner, S Buitink, M Carson, J Casey, M Casier, D Chirkin, B Christy, F Clevermann, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, CD Clercq, F Descamps, P Desiati, GDV Uiterweerd, T DeYoung, JC Díaz-Vélez, J Dreyer, JP Dumm, M Dunkman, R Eagan, J Eisch, RW Ellsworth, O Engdegård, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, R Franke, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, JA Goodman, D Góra, D Grant, A Groß, S Grullon, M Gurtner, C Ha, AH Ismail, A Hallgren, F Halzen, K Hanson, D Heereman, P Heimann, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, GS Japaridze, O Jlelati, A Kappes, T Karg, A Karle, J Kiryluk, F Kislat, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, K Laihem, H Landsman, MJ Larson, R Lauer, M Lesiak-Bzdak, J Lünemann, J Madsen, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, SM Movit, R Nahnhauer, U Naumann, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, M Olivo, A O'Murchadha, S Panknin, L Paul, JA Pepper, CPDL Heros, D Pieloth, N Pirk, J Posselt, PB Price, GT Przybylski, L Rädel, K Rawlins, P Redl, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, F Rothmaier, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schöneberg, L Schönherr, A Schönwald, A Schukraft, L Schulte, O Schulz, D Seckel, SH Seo, Y Sestayo, S Seunarine, MWE Smith, M Soiron, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, GW Sullivan, H Taavola, I Taboada, A Tamburro, S Ter-Antonyan, S Tilav, PA Toale, S Toscano, M Usner, DVD Drift, NV Eijndhoven, AV Overloop, JV Santen, M Vehring, M Voge, C Walck, T Waldenmaier, M Wallraff, M Walter, R Wasserman, C Weaver, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, C Xu, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, A Zilles, M Zoll

We report on searches for neutrino sources at energies above 200 GeV in the Northern sky of the galactic plane, using the data collected by the South Pole neutrino telescopes IceCube and AMANDA. The galactic region considered here includes the Local Arm towards the Cygnus region and our closest approach to the Perseus Arm. The data have been collected between 2007 and 2009 when AMANDA was an integrated part of IceCube, which was still under construction and operated with 22-strings (2007-8) and 40-strings (2008-9) of optical modules deployed in the ice. By combining the larger IceCube detector with the lower energy threshold of the more compact AMANDA detector, we obtain an improved sensitivity at energies below $\sim$10 TeV with respect to previous searches. The analyses presented here are: a scan for point sources within the galactic plane; a search optimized for multiple and extended sources in the Cygnus region, which might be below the sensitivity of the point source scan; and studies of seven pre-selected neutrino source candidates. For one of them, Cygnus X-3, a time-dependent search for neutrinos in coincidence with observed radio and X-ray flares has been performed. No evidence of a signal is found, and upper limits are reported for each of the searches. We investigate neutrino spectra proportional to E$^{-2}$ and E$^{-3}$ to cover the entire range of possible spectra. The soft E$^{-3}$ spectrum results in an energy distribution similar to a source with cut-off below $\sim$50 TeV. For the considered region of the galactic plane, the 90% confidence level muon neutrino flux upper limits are in the range E$^3$dN/dE$\sim 5.4 - 19.5 \times 10^{-11} \rm{TeV^{2} cm^{-2} s^{-1}}$ for point-like neutrino sources in the energy region [180.0 GeV - 20.5 TeV]. These represent the most stringent upper limits for soft-spectra neutrino sources within the Galaxy reported to date.


Cosmological growth and feedback from supermassive black holes

ArXiv (2013)

P Mocz, KM Blundell, AC Fabian

We develop a simple evolutionary scenario for the growth of supermassive black holes (BHs), assuming growth due to accretion only, to learn about the evolution of the BH mass function from $z=3$ to 0 and from it calculate the energy budgets of different modes of feedback. We tune the parameters of the model by matching the derived X-ray luminosity function (XLF) with the observed XLF of active galactic nuclei. We then calculate the amount of comoving kinetic and bolometric feedback as a function of redshift, derive a kinetic luminosity function and estimate the amount of kinetic feedback and $PdV$ work done by classical double Fanaroff-Riley II (FR II) radio sources. We also derive the radio luminosity function for FR IIs from our synthesized population and set constraints on jet duty cycles. Around 1/6 of the jet power from FR II sources goes into $PdV$ work done in the expanding lobes during the time the jet is on. Anti hierarchical growth of BHs is seen in our model due to addition of an amount of mass being accreted on to all BHs independent of the BH mass. The contribution to the total kinetic feedback by active galaxies in a low accretion, kinetically efficient mode is found to be the most significant at $z<1.5$. FR II feedback is found to be a significant mode of feedback above redshifts $z\sim 1.5$, which has not been highlighted by previous studies.


DIFFUSE INTERSTELLAR BAND AT 8620 angstrom IN RAVE: A NEW METHOD FOR DETECTING THE DIFFUSE INTERSTELLAR BAND IN SPECTRA OF COOL STAR

ASTROPHYSICAL JOURNAL 778 (2013) ARTN 86

J Kos, T Zwitter, EK Grebel, O Bienayme, J Binney, J Bland-Hawthorn, KC Freeman, BK Gibson, G Gilmore, G Kordopatis, JF Navarro, Q Parker, WA Reid, G Seabroke, A Siebert, A Siviero, M Steinmetz, F Watson, RFG Wyse


FLASH hydrodynamic simulations of experiments to explore the generation of cosmological magnetic fields

High Energy Density Physics 9 (2013) 75-81

A Scopatz, M Fatenejad, N Flocke, G Gregori, M Koenig, DQ Lamb, D Lee, J Meinecke, A Ravasio, P Tzeferacos, K Weide, R Yurchak

We report the results of FLASH hydrodynamic simulations of the experiments conducted by the University of Oxford High Energy Density Laboratory Astrophysics group and its collaborators at the Laboratoire pour l'Utilisation de Lasers Intenses (LULI). In these experiments, a long-pulse laser illuminates a target in a chamber filled with Argon gas, producing shock waves that generate magnetic fields via the Biermann battery mechanism. The simulations show that the result of the laser illuminating the target is a series of complex hydrodynamic phenomena. © 2012 Elsevier B.V.


Cosmic ray acceleration in young supernova remnants

Monthly Notices of the Royal Astronomical Society 435 (2013) 1174-1185

KM Schure, AR Bell

We investigate the appearance of magnetic field amplification resulting from a cosmic ray escape current in the context of supernova remnant shock waves. The current is inversely proportional to the maximum energy of cosmic rays, and is a strong function of the shock velocity. Depending on the evolution of the shock wave, which is drastically different for different circumstellar environments, the maximum energy of cosmic rays as required to generate enough current to trigger the non-resonant hybrid instability that confines the cosmic rays follows a different evolution and reaches different values.We find that the best candidates to accelerate cosmic rays to ~ few PeV energies are young remnants in a dense environment, such as a red supergiant wind, as may be applicable to Cassiopeia A. We also find that for a typical background magnetic field strength of 5 μG the instability is quenched in about 1000 years, making SN1006 just at the border of candidates for cosmic ray acceleration to high energies. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.


CTA contributions to the 33rd International Cosmic Ray Conference (ICRC2013)

ArXiv (2013)

TCTA Consortium, O Abril, BS Acharya, M Actis, G Agnetta, JA Aguilar, F Aharonian, M Ajello, A Akhperjanian, M Alcubierre, J Aleksic, R Alfaro, E Aliu, AJ Allafort, D Allan, I Allekotte, R Aloisio, E Amato, G Ambrosi, M Ambrosio, J Anderson, EO Angüner, LA Antonelli, V Antonuccio, M Antonucci, P Antoranz, A Aravantinos, A Argan, T Arlen, C Aramo, T Armstrong, H Arnaldi, L Arrabito, K Asano, T Ashton, HG Asorey, T Aune, Y Awane, H Baba, A Babic, N Baby, J Bähr, A Bais, C Baixeras, S Bajtlik, M Balbo, D Balis, C Balkowski, J Ballet, A Bamba, R Bandiera, A Barber, C Barbier, M Barceló, A Barnacka, J Barnstedt, UBD Almeida, JA Barrio, A Basili, S Basso, D Bastieri, C Bauer, A Baushev, U Becciani, J Becerra, J Becerra, Y Becherini, KC Bechtol, JB Tjus, V Beckmann, W Bednarek, B Behera, M Belluso, W Benbow, J Berdugo, D Berge, K Berger, F Bernard, T Bernardino, K Bernlöhr, B Bertucci, N Bhat, S Bhattacharyya, B Biasuzzi, C Bigongiari, A Biland, S Billotta, T Bird, E Birsin, E Bissaldi, J Biteau, M Bitossi, S Blake, OB Bigas, P Blasi, A Bobkov, V Boccone, M Böttcher, L Bogacz, J Bogart, M Bogdan, C Boisson, JB Gargallo, J Bolmont, G Bonanno, A Bonardi, T Bonev, P Bonifacio, G Bonnoli, P Bordas, A Borgland, J Borkowski, R Bose, O Botner, A Bottani, L Bouchet, M Bourgeat, C Boutonnet, A Bouvier, S Brau-Nogué, I Braun, T Bretz, M Briggs, M Brigida, T Bringmann, R Britto, P Brook, P Brun, L Brunetti, P Bruno, N Bucciantini, T Buanes, J Buckley, R Bühler, V Bugaev, A Bulgarelli, T Bulik, G Busetto, S Buson, K Byrum, M Cailles, R Cameron, J Camprecios, R Canestrari, S Cantu, M Capalbi, P Caraveo, E Carmona, A Carosi, R Carosi, J Carr, J Carter, PH Carton, R Caruso, S Casanova, E Cascone, M Casiraghi, A Castellina, O Catalano, S Cavazzani, S Cazaux, P Cerchiara, M Cerruti, E Chabanne, P Chadwick, C Champion, R Chaves, P Cheimets, A Chen, J Chiang, L Chiappetti, M Chikawa, VR Chitnis, F Chollet, A Christof, J Chudoba, M Cieślar, A Cillis, M Cilmo, A Codino, J Cohen-Tanugi, S Colafrancesco, P Colin, J Colome, S Colonges, M Compin, P Conconi, V Conforti, V Connaughton, J Conrad, JL Contreras, P Coppi, J Coridian, P Corona, D Corti, J Cortina, L Cossio, A Costa, H Costantini, G Cotter, B Courty, S Couturier, S Covino, G Crimi, SJ Criswell, J Croston, G Cusumano, M Dafonseca, O Dale, M Daniel, J Darling, I Davids, F Dazzi, AD Angelis, VD Caprio, FD Frondat, EMDGD Pino, IDL Calle, GADL Vega, RDLR Lopez, BD Lotto, AD Luca, MD Naurois, YD Oliveira, EDO Wilhelmi, FD Palma, VD Souza, G Decerprit, G Decock, C Deil, E Delagnes, G Deleglise, C Delgado, DD Volpe, P Demange, G Depaola, A Dettlaff, TD Girolamo, CD Giulio, AD Paola, FD Pierro, GD Sciascio, C Díaz, J Dick, R Dickherber, H Dickinson, V Diez-Blanco, S Digel, D Dimitrov, G Disset, A Djannati-Ataï, M Doert, M Dohmke, W Domainko, DD Prester, A Donat, D Dorner, M Doro, JL Dournaux, G Drake, D Dravins, L Drury, F Dubois, R Dubois, G Dubus, C Dufour, D Dumas, J Dumm, D Durand, V Dwarkadas, J Dyks, M Dyrda, J Ebr, E Edy, K Egberts, P Eger, S Einecke, C Eleftheriadis, S Elles, D Emmanoulopoulos, D Engelhaupt, R Enomoto, JP Ernenwein, M Errando, A Etchegoyen, PA Evans, A Falcone, A Faltenbacher, D Fantinel, K Farakos, C Farnier, E Farrell, G Fasola, BW Favill, E Fede, S Federici, S Fegan, F Feinstein, D Ferenc, P Ferrando, M Fesquet, P Fetfatzis, A Fiasson, E Fillin-Martino, D Fink, C Finley, JP Finley, M Fiorini, RF Curcoll, E Flandrini, H Fleischhack, H Flores, D Florin, W Focke, C Föhr, E Fokitis, L Font, G Fontaine, M Fornasa, A Förster, L Fortson, N Fouque, A Franckowiak, FJ Franco, A Frankowski, C Fransson, GW Fraser, R Frei, L Fresnillo, C Fruck, D Fugazza, Y Fujita, Y Fukazawa, Y Fukui, S Funk, W Gäbele, S Gabici, R Gabriele, A Gadola, N Galante, D Gall, Y Gallant, J Gámez-García, M Garczarczyk, B García, RG López, D Gardiol, F Gargano, D Garrido, L Garrido, D Gascon, M Gaug, J Gaweda, L Gebremedhin, N Geffroy, L Gerard, A Ghedina, M Ghigo, P Ghislain, E Giannakaki, F Gianotti, S Giarrusso, G Giavitto, B Giebels, N Giglietto, V Gika, M Giomi, P Giommi, F Giordano, N Girard, E Giro, A Giuliani, T Glanzman, JF Glicenstein, N Godinovic, V Golev, MG Berisso, J Gómez-Ortega, MM Gonzalez, A González, F González, AG Muñoz, KS Gothe, T Grabarczyk, M Gougerot, R Graciani, P Grandi, F Grañena, J Granot, G Grasseau, R Gredig, A Green, T Greenshaw, T Grégoire, A Grillo, O Grimm, MH Grondin, J Grube, M Grudzinska, V Gruev, S Grünewald, J Grygorczuk, V Guarino, S Gunji, G Gyuk, D Hadasch, A Hagedorn, R Hagiwara, J Hahn, N Hakansson, A Hallgren, NH Heras, S Hara, MJ Hardcastle, D Harezlak, J Harris, T Hassan, K Hatanaka, T Haubold, A Haupt, T Hayakawa, M Hayashida, R Heller, F Henault, G Henri, G Hermann, R Hermel, A Herrero, O Hervet, N Hidaka, JA Hinton, K Hirotani, D Hoffmann, W Hofmann, P Hofverberg, J Holder, JR Hörandel, D Horns, D Horville, J Houles, M Hrabovsky, D Hrupec, H Huan, B Huber, JM Huet, G Hughes, TB Humensky, J Huovelin, JF Huppert, A Ibarra, D Ikawa, JM Illa, D Impiombato, S Incorvaia, S Inoue, Y Inoue, F Iocco, K Ioka, GL Israel, C Jablonski, A Jacholkowska, J Jacquemier, M Jamrozy, M Janiak, P Jean, C Jeanney, JJ Jimenez, T Jogler, C Johnson, T Johnson, L Journet, C Juffroy, I Jung, P Kaaret, S Kabuki, M Kagaya, J Kakuwa, C Kalkuhl, R Kankanyan, A Karastergiou, K Kärcher, M Karczewski, S Karkar, J Kasperek, D Kastana, H Katagiri, J Kataoka, K Katarzyński, U Katz, N Kawanaka, D Kazanas, N Kelley-Hoskins, B Kellner-Leidel, H Kelly, E Kendziorra, B Khélifi, DB Kieda, T Kifune, T Kihm, T Kishimoto, K Kitamoto, W Kluźniak, C Knapic, J Knapp, J Knödlseder, F Köck, J Kocot, K Kodani, JH Köhne, K Kohri, K Kokkotas, D Kolitzus, N Komin, I Kominis, Y Konno, H Köppel, P Korohoda, K Kosack, G Koss, R Kossakowski, R Koul, G Kowal, S Koyama, J Kozioł, T Krähenbühl, J Krause, H Krawzcynski, F Krennrich, A Krepps, A Kretzschmann, R Krobot, P Krueger, H Kubo, VA Kudryavtsev, J Kushida, A Kuznetsov, AL Barbera, NL Palombara, VL Parola, GL Rosa, K Lacombe, G Lamanna, J Lande, D Languignon, JS Lapington, P Laporte, B Laurent, C Lavalley, TL Flour, AL Padellec, SH Lee, WH Lee, JP Lefèvre, H Leich, MALD Oliveira, D Lelas, JP Lenain, R Leoni, DJ Leopold, T Lerch, L Lessio, G Leto, B Lieunard, S Lieunard, R Lindemann, E Lindfors, A Liolios, A Lipniacka, H Lockart, T Lohse, S Lombardi, F Longo, A Lopatin, M Lopez, R López-Coto, A López-Oramas, A Lorca, E Lorenz, F Louis, P Lubinski, F Lucarelli, H Lüdecke, J Ludwin, PL Luque-Escamilla, W Lustermann, O Luz, E Lyard, MC Maccarone, TJ Maccarone, GM Madejski, A Madhavan, M Mahabir, G Maier, P Majumdar, G Malaguti, G Malaspina, S Maltezos, A Manalaysay, A Mancilla, D Mandat, G Maneva, A Mangano, P Manigot, K Mannheim, I Manthos, N Maragos, A Marcowith, M Mariotti, M Marisaldi, S Markoff, A Marszałek, C Martens, J Martí, JM Martin, P Martin, G Martínez, F Martínez, M Martínez, F Massaro, A Masserot, A Mastichiadis, A Mathieu, H Matsumoto, F Mattana, S Mattiazzo, A Maurer, G Maurin, S Maxfield, J Maya, D Mazin, LM Comb, A McCann, N McCubbin, I McHardy, R McKay, K Meagher, C Medina, C Melioli, D Melkumyan, D Melo, S Mereghetti, P Mertsch, M Meucci, M Meyer, J Michałowski, P Micolon, A Mihailidis, T Mineo, M Minuti, N Mirabal, F Mirabel, JM Miranda, R Mirzoyan, A Mistò, T Mizuno, B Moal, R Moderski, I Mognet, E Molinari, M Molinaro, T Montaruli, C Monte, I Monteiro, P Moore, AM Olaizola, M Mordalska, C Morello, K Mori, G Morlino, A Morselli, F Mottez, Y Moudden, E Moulin, I Mrusek, R Mukherjee, P Munar-Adrover, H Muraishi, K Murase, AS Murphy, S Nagataki, T Naito, D Nakajima, T Nakamori, K Nakayama, C Naumann, D Naumann, M Naumann-Godo, P Nayman, D Nedbal, D Neise, L Nellen, A Neronov, V Neustroev, N Neyroud, L Nicastro, J Nicolau-Kukliński, A Niedźwiecki, J Niemiec, D Nieto, A Nikolaidis, K Nishijima, KI Nishikawa, K Noda, S Nolan, R Northrop, D Nosek, N Nowak, A Nozato, L Oakes, PT O'Brien, Y Ohira, M Ohishi, S Ohm, H Ohoka, T Okuda, A Okumura, JF Olive, RA Ong, R Orito, M Orr, JP Osborne, M Ostrowski, LA Otero, N Otte, E Ovcharov, I Oya, A Ozieblo, L Padilla, I Pagano, S Paiano, D Paillot, A Paizis, S Palanque, M Palatka, J Pallota, M Palatiello, K Panagiotidis, JL Panazol, D Paneque, M Panter, MR Panzera, R Paoletti, A Papayannis, G Papyan, JM Paredes, G Pareschi, JM Parraud, D Parsons, G Pauletta, MP Arribas, M Pech, G Pedaletti, V Pelassa, D Pelat, MDC Perez, M Persic, PO Petrucci, B Peyaud, A Pichel, D Pieloth, E Pierre, S Pita, G Pivato, F Pizzolato, M Platino, Ł Platos, R Platzer, S Podkladkin, L Pogosyan, M Pohl, G Pojmanski, JD Ponz, W Potter, J Poutanen, E Prandini, J Prast, R Preece, F Profeti, H Prokoph, M Prouza, M Proyetti, I Puerto-Giménez, G Pühlhofer, I Puljak, M Punch, R Pyzioł, EJ Quel, J Quesada, J Quinn, A Quirrenbach, E Racero, S Rainò, PJ Rajda, M Rameez, P Ramon, R Rando, RC Rannot, M Rataj, M Raue, D Ravignani, P Reardon, O Reimann, A Reimer, O Reimer, K Reitberger, M Renaud, S Renner, B Reville, W Rhode, M Ribó, M Ribordy, G Richards, MG Richer, J Rico, J Ridky, F Rieger, P Ringegni, J Ripken, PR Ristori, A Rivière, S Rivoire, L Rob, G Rodeghiero, U Roeser, R Rohlfs, G Rojas, P Romano, W Romaszkan, GE Romero, SR Rosen, SR Lees, D Ross, G Rouaix, J Rousselle, S Rousselle, AC Rovero, F Roy, S Royer, B Rudak, C Rulten, M Rupiński, F Russo, F Ryde, O Saavedra, B Sacco, EO Saemann, A Saggion, V Sahakian, K Saito, T Saito, Y Saito, N Sakaki, R Sakonaka, A Salini, F Sanchez, M Sanchez-Conde, A Sandoval, H Sandaker, E Sant'Ambrogio, A Santangelo, EM Santos, A Sanuy, L Sapozhnikov, S Sarkar, N Sartore, H Sasaki, K Satalecka, M Sawada, V Scalzotto, V Scapin, M Scarcioffolo, J Schafer, T Schanz, S Schlenstedt, R Schlickeiser, T Schmidt, J Schmoll, P Schovanek, M Schroedter, A Schubert, C Schultz, J Schultze, A Schulz, K Schure, F Schussler, T Schwab, U Schwanke, J Schwarz, S Schwarzburg, T Schweizer, S Schwemmer, U Schwendicke, C Schwerdt, A Segreto, JH Seiradakis, GH Sembroski, M Servillat, K Seweryn, M Sharma, M Shayduk, RC Shellard, J Shi, T Shibata, A Shibuya, S Shore, E Shum, E Sideras-Haddad, L Sidoli, M Sidz, J Sieiro, M Sikora, J Silk, A Sillanpää, BB Singh, G Sironi, J Sitarek, C Skole, R Smareglia, A Smith, D Smith, J Smith, N Smith, D Sobczyńska, H Sol, G Sottile, M Sowiński, F Spanier, D Spiga, S Spyrou, V Stamatescu, A Stamerra, RLC Starling, Ł Stawarz, R Steenkamp, C Stegmann, S Steiner, C Stella, N Stergioulas, R Sternberger, M Sterzel, F Stinzing, M Stodulski, T Stolarczyk, U Straumann, E Strazzeri, L Stringhetti, A Suarez, M Suchenek, R Sugawara, KH Sulanke, S Sun, AD Supanitsky, T Suric, P Sutcliffe, JM Sykes, M Szanecki, T Szepieniec, A Szostek, G Tagliaferri, H Tajima, H Takahashi, K Takahashi, L Takalo, H Takami, G Talbot, J Tammi, M Tanaka, S Tanaka, J Tasan, M Tavani, JP Tavernet, LA Tejedor, I Telezhinsky, P Temnikov, C Tenzer, Y Terada, R Terrier, M Teshima, V Testa, D Tezier, J Thayer, D Thuermann, L Tibaldo, L Tibaldo, O Tibolla, A Tiengo, MC Timpanaro, M Tluczykont, CJT Peixoto, F Tokanai, M Tokarz, K Toma, A Tonachini, K Torii, M Tornikoski, DF Torres, M Torres, S Toscano, G Toso, G Tosti, T Totani, F Toussenel, G Tovmassian, P Travnicek, A Treves, M Trifoglio, I Troyano, K Tsinganos, H Ueno, G Umana, K Umehara, SS Upadhya, T Usher, M Uslenghi, F Vagnetti, JF Valdes-Galicia, P Vallania, G Vallejo, WV Driel, CV Eldik, J Vandenbrouke, J Vanderwalt, H Vankov, G Vasileiadis, V Vassiliev, D Veberic, I Vegas, S Vercellone, S Vergani, V Verzi, GP Vettolani, C Veyssière, JP Vialle, A Viana, M Videla, C Vigorito, P Vincent, S Vincent, J Vink, N Vlahakis, L Vlahos, P Vogler, V Voisin, A Vollhardt, HPV Gunten, S Vorobiov, C Vuerli, V Waegebaert, R Wagner, RG Wagner, S Wagner, SP Wakely, R Walter, T Walther, K Warda, RS Warwick, P Wawer, R Wawrzaszek, N Webb, P Wegner, A Weinstein, Q Weitzel, R Welsing, M Werner, H Wetteskind, RJ White, A Wierzcholska, S Wiesand, A Wilhelm, MI Wilkinson, DA Williams, R Willingale, M Winde, K Winiarski, R Wischnewski, Ł Wiśniewski, P Wojcik, M Wood, A Wörnlein, Q Xiong, KK Yadav, H Yamamoto, T Yamamoto, R Yamazaki, S Yanagita, JM Yebras, D Yelos, A Yoshida, T Yoshida, T Yoshikoshi, P Yu, V Zabalza, M Zacharias, A Zajczyk, L Zampieri, R Zanin, A Zdziarski, A Zech, A Zhao, X Zhou, K Zietara, J Ziolkowski, P Ziółkowski, V Zitelli, C Zurbach, P Zychowski

Compilation of CTA contributions to the proceedings of the 33rd International Cosmic Ray Conference (ICRC2013), which took place in 2-9 July, 2013, in Rio de Janeiro, Brazil


Impact of extended preplasma on energy coupling in kilojoule energy relativistic laser interaction with cone wire targets relevant to fast ignition

New Journal of Physics 15 (2013)

T Yabuuchi, R Mishra, C McGuffey, B Qiao, MS Wei, H Sawada, Y Sentoku, T Ma, DP Higginson, KU Akli, D Batani, H Chen, LA Gizzi, MH Key, AJ MacKinnon, HS McLean, PA Norreys, PK Patel, RB Stephens, Y Ping, W Theobald, C Stoeckl, FN Beg

Cone-guided fast ignition laser fusion depends critically on details of the interaction of an intense laser pulse with the inside tip of a cone. Generation of relativistic electrons in the laser plasma interaction (LPI) with a gold cone and their subsequent transport into a copper wire have been studied using a kJ-class intense laser pulse, OMEGA EP (850 J, 10 ps). Weobserved that the laser-pulse-energy-normalized copper K signal from the Cu wire attached to the Au cone is significantly reduced (by a factor of 5) as compared to that from identical targets using the Titan laser (150 J, 0.7 ps) with 60 × less energy in the prepulse. We conclude that the decreased coupling is due to increased prepulse energy rather than 10 ps pulse duration, for which this effect has not been previously explored. The collisional particle-in-cell code PICLS demonstrates that the preformed plasma has a significant impact on generation of electrons and their transport. In particular, a longer scale length preplasma significantly reduces the energy coupling from the intense laser to the wire due to the larger offset distance between the relativistic critical density surface and the cone tip as well as a wider divergence of source electrons. We also observed that laser-driven plasma ionization increase in the LPI region can potentially alter the electron density profile during the laser interaction, forcing the electron source to be moved farther away from the cone tip which contributes to the reduction of energy coupling. © IOP Publishing and Deutsche Physikalische Gesellschaft.


The role of collisions on mode competition between the two-stream and Weibel instabilities

Journal of Plasma Physics 79 (2013) 987-989

KA Humphrey, DC Speirs, R Bingham, RMGM Trines, P Norreys

We present results from numerical simulations conducted to investigate a potential method for realizing the required fusion fuel heating in the fast ignition scheme to achieving inertial confinement fusion. A comparison will be made between collisionless and collisional particle-in-cell simulations of the relaxation of a non-thermal electron beam through the two-stream instability. The results presented demonstrate energy transfer to the plasma ion population from the laser-driven electron beam via the nonlinear wave-wave interaction associated with the two-stream instability. Evidence will also be provided for the effects of preferential damping of competing instabilities such as the Weibel mode found to be detrimental to the ion heating process. © Cambridge University Press 2013.