Publications


The Gaia-ESO Survey: processing FLAMES-UVES spectra

ASTRONOMY & ASTROPHYSICS 565 (2014) ARTN A113

GG Sacco, L Morbidelli, E Franciosini, E Majorca, S Randich, A Modigliani, G Gilmore, M Asplund, J Binney, P Bordfacio, J Drew, S Feltzing, A Ferguson, R Jeffries, G Micela, I Negueruela, T Prusti, H-W Rix, A Vallenari, E Alfaro, CA Prieto, C Babusiaux, T Bensby, R Blomme, A Bragaglia, E Flaccomio, P Francois, N Hambly, M Irwin, S Koposov, A Korn, A Lanzafame, F Pancino, A Recio-Blanco, R Smiljanic, S Van Eck, N Walton, M Bergemann, MT Costado, P de Laverny, U Heiter, V Hill, A Hourihane, R Jackson, P Jofre, J Lewis, K Lind, C Lardo, L Magrini, T Masseron, L Prisinzano, C Worley


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.


Comparison of BES measurements of ion-scale turbulence with direct gyro-kinetic simulations of MAST L-mode plasmas

Plasma Physics and Controlled Fusion 56 (2014)

AR Field, D Dunai, Y-C Ghim, P Hill, B McMillan, CM Roach, S Saarelma, AA Schekochihin, S Zoletnik

Observations of ion-scale (kyρi 1) density turbulence of relative amplitude 0.2% are available on the Mega Amp Spherical Tokamak (MAST) using a 2D (8 radial × 4 poloidal channel) imaging beam emission spectroscopy diagnostic. Spatial and temporal characteristics of this turbulence, i.e., amplitudes, correlation times, radial and perpendicular correlation lengths and apparent phase velocities of the density contours, are determined by means of correlation analysis. For a low-density, L-mode discharge with strong equilibrium flow shear exhibiting an internal transport barrier in the ion channel, the observed turbulence characteristics are compared with synthetic density turbulence data generated from global, non-linear, gyro-kinetic simulations using the particle-in-cell code NEMORB. This validation exercise highlights the need to include increasingly sophisticated physics, e.g., kinetic treatment of trapped electrons, equilibrium flow shear and collisions, to reproduce most of the characteristics of the observed turbulence. Even so, significant discrepancies remain: an underprediction by the simulations of the turbulence amplitude and heat flux at plasma periphery and the finding that the correlation times of the numerically simulated turbulence are typically two orders of magnitude longer than those measured in MAST. Comparison of these correlation times with various linear timescales suggests that, while the measured turbulence is strong and may be 'critically balanced', the simulated turbulence is weak. © 2014 IOP Publishing Ltd.


On the maximum energy of shock-accelerated cosmic rays at ultra-relativistic shocks

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 439 (2014) 2050-2059

B Reville, AR Bell


AMS-02 data confronts acceleration of cosmic ray secondaries in nearby sources

ArXiv (2014)

P Mertsch, S Sarkar

We revisit the model proposed earlier to account for the observed increase in the positron fraction in cosmic rays with increasing energy, in the light of new data from the Alpha Magnetic Spectrometer (AMS-02) experiment. The model accounts for the production and acceleration of secondary electrons and positrons in nearby supernova remnants which results in an additional, harder component that becomes dominant at high energies. By fitting this to AMS-02 data we can calculate the expected concomitant rise of the boron-to-carbon ratio, as well as of the fraction of antiprotons. If these predictions are confirmed by the forthcoming AMS-02 data it would conclusively rule out all other proposed explanations, in particular dark matter annihilations or decays.


Searches for small-scale anisotropies from neutrino point sources with three years of IceCube data

ArXiv (2014)

I Collaboration, MG Aartsen, M Ackermann, J Adams, JA Aguilar, M Ahlers, M Ahrens, D Altmann, T Anderson, C Arguelles, TC Arlen, J Auffenberg, X Bai, SW Barwick, V Baum, 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, F Bos, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, J Casey, M Casier, E Cheung, D Chirkin, A Christov, B Christy, K Clark, L Classen, F Clevermann, S Coenders, 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, J Felde, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, R Gaior, J Gallagher, L Gerhardt, D Gier, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, D Grant, P Gretskov, JC Groh, A Groß, C Ha, C Haack, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Hebecker, D Heereman, D Heinen, K Helbing, R Hellauer, D Hellwig, 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, M Jurkovic, B Kaminsky, A Kappes, T Karg, A Karle, M Kauer, JL Kelley, A Kheirandish, J Kiryluk, J Kläs, SR Klein, JH Köhne, G Kohnen, H Kolanoski, A Koob, L Köpke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, A Kriesten, K Krings, G Kroll, M Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, DT Larsen, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Lünemann, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, R Maunu, F McNally, K Meagher, M Medici, A Meli, T Meures, S Miarecki, E Middell, E Middlemas, 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, Ö Penek, JA Pepper, CPDL Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, J Pütz, M Quinnan, L Rädel, M Rameez, K Rawlins, P Redl, I Rees, R Reimann, M Relich, E Resconi, W Rhode, M Richman, B Riedel, S Robertson, JP Rodrigues, M Rongen, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, HG Sander, J Sandroos, 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, 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, A Terliuk, G Tešić, S Tilav, PA Toale, MN Tobin, D Tosi, M Tselengidou, E Unger, M Usner, S Vallecorsa, NV Eijndhoven, J Vandenbroucke, JV Santen, M Vehring, M Voge, M Vraeghe, C Walck, M Wallraff, C Weaver, M Wellons, C Wendt, S Westerhoff, BJ Whelan, N Whitehorn, C Wichary, 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

Recently, IceCube found evidence for a diffuse signal of astrophysical neutrinos in an energy range of $60\,\mathrm{TeV}$ to the $\mathrm{PeV}$-scale. The origin of those events, being a key to understanding the origin of cosmic rays, is still an unsolved question. So far, analyses have not succeeded to resolve the diffuse signal into point-like sources. Searches including a maximum-likelihood-ratio test, based on the reconstructed directions and energies of the detected down- and up-going neutrino candidates, were also performed on IceCube data leading to the exclusion of bright point sources. In this paper, we present two methods to search for faint neutrino point sources in three years of IceCube data, taken between 2008 and 2011. The first method is an autocorrelation test, applied separately to the northern and southern sky. The second method is a multipole analysis, which expands the measured data in the northern hemisphere into spherical harmonics and uses the resulting expansion coefficients to separate signal from background. With both methods, the results are consistent with the background expectation with a slightly more sparse spatial distribution, corresponding to an underfluctuation. Depending on the assumed number of sources, the resulting upper limit on the flux per source in the northern hemisphere for an $E^{-2}$ energy spectrum ranges from $1.5 \cdot 10^{-8}\,\mathrm{GeV}/(\mathrm{cm}^2 \mathrm{s})$, in the case of one assumed source, to $4 \cdot 10^{-10} \,\mathrm{GeV}/(\mathrm{cm}^2 \mathrm{s})$, in the case of $3500$ assumed sources.


The second data release of the INT Photometric Ha Survey of the Northern Galactic Plane (IPHAS DR2)

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 444 (2014) 3230-3257

G Barentsen, HJ Farnhill, JE Drew, EA Gonzalez-Solares, R Greimel, MJ Irwin, B Miszalski, C Ruhland, P Groot, A Mampaso, SE Sale, AA Henden, A Aungwerojwit, MJ Barlow, PJ Carter, RLM Corradi, JJ Drake, J Eisloeffel, J Fabregat, BT Gaensicke, NPG Fusillo, S Greiss, AS Hales, S Hodgkin, L Huckvale, J Irwin, R King, C Knigge, T Kupfer, E Lagadec, DJ Lennon, JR Lewis, M Mohr-Smith, RAH Morris, T Naylor, QA Parker, S Phillipps, S Pyrzas, R Raddi, GHA Roelofs, P Rodriguez-Gil, L Sabin, S Scaringi, D Steeghs, J Suso, R Tata, YC Unruh, J van Roestel, K Viironen, JS Vink, NA Walton, NJ Wright, AA Zijlstra


The ATLAS(3D) project - XXVII. Cold gas and the colours and ages of early-type galaxies

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 444 (2014) 3408-3426

LM Young, N Scott, P Serra, K Alatalo, E Bayet, L Blitz, M Bois, F Bournaud, M Bureau, AF Crocker, M Cappellari, RL Davies, TA Davis, PT de Zeeuw, P-A Duc, E Emsellem, S Khochfar, D Krajnovic, H Kuntschner, RM McDermid, R Morganti, T Naab, T Oosterloo, M Sarzi, A-M Weijmans


Proton-driven plasma wakefield acceleration: A path to the future of high-energy particle physics

Plasma Physics and Controlled Fusion Institute of Physics Publishing 56 (2014)

R Assmann, R Bingham, T Bohl, C Bracco, B Buttenschön, A Butterworth, A Caldwell, S Chattopadhyay, S Cipiccia, E Feldbaumer, RA Fonseca, B Goddard, M Gross, O Grulke, E Gschwendtner, J Holloway, C Huang, D Jaroszynski, S Jolly, P Kempkes, N Lopes, K Lotov, J Machacek, SR Mandry, JW McKenzie, M Meddahi, BL Militsyn, N Moschuering, P Muggli, Z Najmudin, TCQ Noakes, PA Norreys, E Öz, A Pardons, A Petrenko, A Pukhov, K Rieger, O Reimann, H Ruhl, E Shaposhnikova, LO Silva, A Sosedkin, R Tarkeshian, RMGN Trines, T Tückmantel, J Vieira, H Vincke, M Wing, G Xia

New acceleration technology is mandatory for the future elucidation of fundamental particles and their interactions. A promising approach is to exploit the properties of plasmas. Past research has focused on creating large-amplitude plasma waves by injecting an intense laser pulse or an electron bunch into the plasma. However, the maximum energy gain of electrons accelerated in a single plasma stage is limited by the energy of the driver. Proton bunches are the most promising drivers of wakefields to accelerate electrons to the TeV energy scale in a single stage. An experimental program at CERN - the AWAKE experiment - has been launched to study in detail the important physical processes and to demonstrate the power of proton-driven plasma wakefield acceleration. Here we review the physical principles and some experimental considerations for a future proton-driven plasma wakefield accelerator. © 2014 IOP Publishing Ltd.


Producing bright X-rays for imaging applications using a laser wakefield accelerator

Optics InfoBase Conference Papers Optical Society of American (OSA) (2014)

SPD Mangles, MS Bloom, J Bryant, JM Cole, A Döpp, S Kneip, H Nakamura, K Poder, MJV Streeter, J Wood, Z Najmudin, R Bendoyro, J Jiang, NC Lopes, C Russo, O Cheklov, K Ertel, SJ Hawkes, CJ Hooker, D Neely, PA Norreys, PP Rajeev, DR Rusby, RHH Scott, DR Symes, J Holloway, M Wing, JF Seely

We report on the generation of bright multi-keV betatron X-ray radiation using a GeV laser wakefield accelerator and investigate the use of these X-rays for various imaging applications. © 2014 Optical Society of America.


Intrinsic alignment of simulated galaxies in the cosmic web: implications for weak lensing surveys

ArXiv (2014)

S Codis, R Gavazzi, Y Dubois, C Pichon, K Benabed, V Desjacques, D Pogosyan, J Devriendt, A Slyz

The intrinsic alignment of galaxy shapes (by means of their angular momentum) and their cross-correlation with the surrounding dark matter tidal field are investigated using the 160 000, z=1.2 synthetic galaxies extracted from the high-resolution cosmological hydrodynamical simulation Horizon-AGN. One- and two-point statistics of the spin of the stellar component are measured as a function of mass and colour. For the low-mass galaxies, this spin is locally aligned with the tidal field `filamentary' direction while, for the high-mass galaxies, it is perpendicular to both filaments and walls. The bluest galaxies of our synthetic catalog are more strongly correlated with the surrounding tidal field than the reddest galaxies, and this correlation extends up to 10 Mpc/h comoving distance. We also report a correlation of the projected ellipticities of blue, intermediate mass galaxies on a similar scale at a level of 10^(-4) which could be a concern for cosmic shear measurements. We do not report any measurable intrinsic alignments of the reddest galaxies of our sample. This work is a first step toward the use of very realistic catalog of synthetic galaxies to evaluate the contamination of weak lensing measurement by the intrinsic galactic alignments.


Observations of strong ion-ion correlations in dense plasmas

PHYSICS OF PLASMAS 21 (2014) ARTN 056302

T Ma, L Fletcher, A Pak, DA Chapman, RW Falcone, C Fortmann, E Galtier, DO Gericke, G Gregori, J Hastings, OL Landen, S Le Pape, HJ Lee, B Nagler, P Neumayer, D Turnbull, J Vorberger, TG White, K Wuensch, U Zastrau, SH Glenzer, T Doeppner


Measurement of South Pole ice transparency with the IceCube LED calibration system

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, AM Brown, R Bruijn, J Brunner, S Buitink, M Carson, J Casey, M Casier, D Chirkin, B Christy, K Clark, F Clevermann, 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, JA Goodman, D Góra, D Grant, A Groß, 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, 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, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, 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, 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, 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, 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, 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, C Xu, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, A Zilles, M Zoll

The IceCube Neutrino Observatory, approximately 1 km^3 in size, is now complete with 86 strings deployed in the Antarctic ice. IceCube detects the Cherenkov radiation emitted by charged particles passing through or created in the ice. To realize the full potential of the detector, the properties of light propagation in the ice in and around the detector must be well understood. This report presents a new method of fitting the model of light propagation in the ice to a data set of in-situ light source events collected with IceCube. The resulting set of derived parameters, namely the measured values of scattering and absorption coefficients vs. depth, is presented and a comparison of IceCube data with simulations based on the new model is shown.


Correlations at large scales and the onset of turbulence in the fast solar WIND

Astrophysical Journal Institute of Physics Publishing 778 (2013)

RT Wicks, DA Roberts, A Mallet, AA Schekochihin, TS Horbury, CHK Chen

We show that the scaling of structure functions of magnetic and velocity fields in a mostly highly Alfvénic fast solar wind stream depends strongly on the joint distribution of the dimensionless measures of cross helicity and residual energy. Already at very low frequencies, fluctuations that are both more balanced (cross helicity ∼0) and equipartitioned (residual energy ∼0) have steep structure functions reminiscent of "turbulent" scalings usually associated with the inertial range. Fluctuations that are magnetically dominated (residual energy ∼-1), and so have closely anti-aligned Elsasser-field vectors, or are imbalanced (cross helicity ∼1), and so have closely aligned magnetic and velocity vectors, have wide "1/f" ranges typical of fast solar wind. We conclude that the strength of nonlinear interactions of individual fluctuations within a stream, diagnosed by the degree of correlation in direction and magnitude of magnetic and velocity fluctuations, determines the extent of the 1/f region observed, and thus the onset scale for the turbulent cascade. © 2013. The American Astronomical Society. All rights reserved.


The IceCube Neutrino Observatory Part II: Atmospheric and Diffuse UHE Neutrino Searches of All Flavors

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 atmospheric and diffuse UHE neutrino searches of all flavors submitted to the 33nd International Cosmic Ray Conference (Rio de Janeiro 2013) by the IceCube Collaboration.


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.


Dynamics for Galactic Archaeology

ArXiv (2013)

J Binney

Our Galaxy is a complex machine in which several processes operate simultaneously: metal-poor gas is accreted, is chemically enriched by dying stars, and then drifts inwards, surrendering its angular momentum to stars; new stars are formed on nearly circular orbits in the equatorial plane and then diffuse through orbit space to eccentric and inclined orbits; the central stellar bar surrenders angular momentum to the surrounding disc and dark halo while acquiring angular momentum from inspiralling gas; the outer parts of the disc are constantly disturbed by satellite objects, both luminous and dark, as they sweep through pericentre. We review the conceptual tools required to bring these complex happenings into focus. Our first concern must be the construction of equilibrium models of the Galaxy, for upon these hang our hopes of determining the Galaxy's mean gravitational field, which is required for every subsequent step. Ideally our equilibrium model should be formulated so that the secular evolution of the system can be modelled with perturbation theory. Such theory can be used to understand how stars diffuse through orbit space from either the thin gas disc in which we presume disc stars formed, or the debris of an accreted object, the presumed origin of many halo stars. Coupling this understanding to the still very uncertain predictions of the theory of stellar evolution and nucleosynthesis, we can finally extract a complete model of the chemodynamic evolution of our reasonably generic Galaxy. We discuss the relation of such a model to cosmological simulations of galaxy formation, which provide general guidance but cannot be relied on for quantitative detail.


All-particle cosmic ray energy spectrum measured with 26 IceTop stations

ArXiv (2012)

I Collaboration, R Abbasi, Y Abdou, T Abu-Zayyad, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, K Andeen, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JLB Alba, K Beattie, JJ Beatty, S Bechet, JK Becker, 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, S Buitink, KS Caballero-Mora, M Carson, M Casier, D Chirkin, B Christy, F Clevermann, S Cohen, DF Cowen, AHC Silva, MV D'Agostino, M Danninger, J Daughhetee, JC Davis, CD Clercq, T Degner, F Descamps, P Desiati, GD Vries-Uiterweerd, T DeYoung, JC Díaz-Vélez, J Dreyer, JP Dumm, M Dunkman, 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, 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 Han, K Hanson, P Heimann, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, B Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, GS Japaridze, H Johansson, A Kappes, T Karg, A Karle, J Kiryluk, F Kislat, SR Klein, S Klepser, JH Köhne, G Kohnen, H Kolanoski, L Köpke, 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, J Lünemann, J Madsen, R Maruyama, K Mase, HS Matis, K Meagher, M Merck, P Mészáros, T Meures, S Miarecki, E Middell, N Milke, J Miller, T Montaruli, R Morse, SM Movit, R Nahnhauer, JW Nam, U Naumann, SC Nowicki, DR Nygren, S Odrowski, A Olivas, M Olivo, A O'Murchadha, S Panknin, L Paul, CPDL Heros, D Pieloth, J Posselt, PB Price, GT Przybylski, K Rawlins, P Redl, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, F Rothmaier, C Rott, T Ruhe, D Rutledge, B Ruzybayev, D Ryckbosch, HG Sander, M Santander, S Sarkar, K Schatto, M Scheel, T Schmidt, S Schöneberg, A Schönwald, A Schukraft, L Schulte, A Schultes, O Schulz, M Schunck, D Seckel, B Semburg, SH Seo, Y Sestayo, S Seunarine, A Silvestri, MWE Smith, GM Spiczak, C Spiering, M Stamatikos, T Stanev, T Stezelberger, RG Stokstad, A Stößl, EA Strahler, R Ström, M Stüer, GW Sullivan, H Taavola, I Taboada, A Tamburro, S Ter-Antonyan, S Tilav, PA Toale, S Toscano, D Tosi, 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, R Wischnewski, H Wissing, M Wolf, TR Wood, K Woschnagg, C Xu, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, M Zoll

We report on a measurement of the cosmic ray energy spectrum with the IceTop air shower array, the surface component of the IceCube Neutrino Observatory at the South Pole. The data used in this analysis were taken between June and October, 2007, with 26 surface stations operational at that time, corresponding to about one third of the final array. The fiducial area used in this analysis was 0.122 km^2. The analysis investigated the energy spectrum from 1 to 100 PeV measured for three different zenith angle ranges between 0{\deg} and 46{\deg}. Because of the isotropy of cosmic rays in this energy range the spectra from all zenith angle intervals have to agree. The cosmic-ray energy spectrum was determined under different assumptions on the primary mass composition. Good agreement of spectra in the three zenith angle ranges was found for the assumption of pure proton and a simple two-component model. For zenith angles {\theta} < 30{\deg}, where the mass dependence is smallest, the knee in the cosmic ray energy spectrum was observed between 3.5 and 4.32 PeV, depending on composition assumption. Spectral indices above the knee range from -3.08 to -3.11 depending on primary mass composition assumption. Moreover, an indication of a flattening of the spectrum above 22 PeV were observed.


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.


Analysing surveys of our Galaxy - II. Determining the potential

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 433 (2013) 1411-1424

PJ McMillan, JJ Binney