| Records |
| Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
| Title |
Antennas for the detection of radio emission pulses from cosmic-ray induced air showers at the Pierre Auger Observatory |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
7 |
Issue |
|
Pages |
P10011 - 49pp |
| Keywords |
Large detector systems for particle and astroparticle physics; Antennas |
Abstract  |
The Pierre Auger Observatory is exploring the potential of the radio detection technique to study extensive air showers induced by ultra-high energy cosmic rays. The Auger Engineering Radio Array (AERA) addresses both technological and scientific aspects of the radio technique. A first phase of AERA has been operating since September 2010 with detector stations observing radio signals at frequencies between 30 and 80 MHz. In this paper we present comparative studies to identify and optimize the antenna design for the final configuration of AERA consisting of 160 individual radio detector stations. The transient nature of the air shower signal requires a detailed description of the antenna sensor. As the ultra-wideband reception of pulses is not widely discussed in antenna literature, we review the relevant antenna characteristics and enhance theoretical considerations towards the impulse response of antennas including polarization effects and multiple signal reflections. On the basis of the vector effective length we study the transient response characteristics of three candidate antennas in the time domain. Observing the variation of the continuous galactic background intensity we rank the antennas with respect to the noise level added to the galactic signal. |
| Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, Lisbon, Portugal |
| Corporate Author |
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Thesis |
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| Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1748-0221 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000310834800021 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1276 |
| Permanent link to this record |
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| Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
| Title |
The rapid atmospheric monitoring system of the Pierre Auger Observatory |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
7 |
Issue |
|
Pages |
P09001 - 41pp |
| Keywords |
Large detector systems for particle and astroparticle physics; Real-time monitoring; Control and monitor systems online |
| Abstract |
The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10(17) eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shortly after the detection of air showers of special interest, e. g., showers produced by very high-energy cosmic rays or showers with atypical longitudinal profiles. The former events are of particular importance for the determination of the energy scale of the Observatory, and the latter are characteristic of unusual air shower physics or exotic primary particle types. The purpose of targeted (or “rapid”) monitoring is to improve the resolution of the atmospheric measurements for such events. In this paper, we report on the implementation of the rapid monitoring program and its current status. The rapid monitoring data have been analyzed and applied to the reconstruction of air showers of high interest, and indicate that the air fluorescence measurements affected by clouds and aerosols are effectively corrected using measurements from the regular atmospheric monitoring program. We find that the rapid monitoring program has potential for supporting dedicated physics analyses beyond the standard event reconstruction. |
| Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, P-1100 Lisbon, Portugal |
| Corporate Author |
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Thesis |
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| Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1748-0221 |
ISBN |
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Medium |
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| Area |
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Expedition |
|
Conference |
|
| Notes |
WOS:000309547100003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1233 |
| Permanent link to this record |
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| Author |
Nanova, M. et al; Oset, E. |
| Title |
Transparency ratio in gamma A -> eta ' A ' and the in-medium eta ' width |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
710 |
Issue |
4-5 |
Pages |
600-606 |
| Keywords |
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| Abstract |
The photoproduction of eta'-mesons off different nuclei has been measured with the CBELSA/TAPS detector system for incident photon energies between 1500-2200 MeV. The transparency ratio has been deduced and compared to theoretical calculations describing the propagation of eta'-mesons in nuclei. The comparison indicates a width of the eta'-meson of the order of Gamma = 15-25 MeV at rho = rho(0) for an average momentum p(eta') = 1050 MeV/c, at which the eta'-meson is produced in the nuclear rest frame. The inelastic eta'N cross section is estimated to be 3-10 mb. Parameterizing the photoproduction cross section of eta'-mesons by sigma(A) = sigma(0)A(alpha), a value of alpha = 0.84 +/- 0.03 has been deduced. |
| Address |
[Nanova, M.; Metag, V.; Makonyi, K.; Gregor, R.; Lugert, S.; Novotny, R.; Pant, L. M.; Pfeiffer, M.; Roy, A.; Schadmand, S.; Trnka, D.; Varma, R.] Univ Giessen, Inst Phys 2, D-35390 Giessen, Germany, Email: mariana.nanova@exp2.physik.uni-giessen.de |
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Thesis |
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| Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0370-2693 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000303221800012 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1008 |
| Permanent link to this record |
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| Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
| Title |
Precision Measurement of the B -> Xs gamma Photon Energy Spectrum, Branching Fraction, and Direct CP Asymmetry ACP(B -> Xs+d gamma) |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
109 |
Issue |
19 |
Pages |
191801 - 8pp |
| Keywords |
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| Abstract |
The photon spectrum in the inclusive electromagnetic radiative decays of the B meson, B --> X-s gamma plus B --> X-d gamma, is studied using a data sample of (382.8 +/- 4.2) x 10(6)Y(4S) --> B (B) over bar decays collected by the BABAR experiment at SLAC. The spectrum is used to extract the branching fraction B(B --> X-s gamma) = (3.21 +/- 0.33) x 10(-4) for E-gamma > 1.8 GeV and the direct CP asymmetry A(CP)(B --> Xs+d gamma) = 0.057 +/- 0.063. The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the B meson rest frame. |
| Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000310869600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1259 |
| Permanent link to this record |
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| Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
| Title |
Measurement of B (B -> Xs gamma), the B -> Xs gamma photon energy spectrum, and the direct CP asymmetry in B -> Xs+d gamma decays |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
86 |
Issue |
11 |
Pages |
112008 - 33pp |
| Keywords |
|
| Abstract |
The photon spectrum in B -> X-s gamma decay, where X-s is any strange hadronic state, is studied using a data sample of (382.8 +/- 4.2) x 10(6) e(+)e(-) -> Upsilon(4S) -> B (B) over bar events collected by the BABAR experiment at the PEP-II collider. The spectrum is used to measure the branching fraction B(B -> X-s gamma) (3.21 +/- 0.15 +/- 0.29 +/- 0.08) x 10(-4) and the first, second, and third moments < E-gamma > = 2.267 +/- 0.019 +/- 0.032 +/- 0.003 GeV, <(E-gamma – < E-gamma >)(2)> = 0.0484 +/- 0.0053 +/- 0.0077 +/- 0.0005 GeV2, and <(E-gamma – < E-gamma)(3)> = -0.0048 +/- 0.0011 +/- 0.0011 +/- 0.0004 GeV3, for the range E-gamma > 1.8 GeV, where E-gamma is the photon energy in the B-meson rest frame. Results are also presented for narrower E-gamma ranges. In addition, the direct CP asymmetry A(CP)(B -> Xs+d gamma) is measured to be 0.057 +/- 0.063. The spectrum itself is also unfolded to the B-meson rest frame; that is the frame in which theoretical predictions for its shape are made. |
| Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000312835600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1281 |
| Permanent link to this record |
