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52. Milagro limits and HAWC sensitivity for the rate-density of evaporating Primordial Black Holes

Author

Abdo, AA, Abeysekara, AU, Alfaro, R, Allen, BT, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Aune, T, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Gonzalez, J Becerra, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Christopher, GE, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Hernandez, R Diaz, Diaz-Cruz, L, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Harding, JP, Hays, E, Hoffman, CM, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kolterman, BE, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-GarcIa, R, MacGibbon, JH, Marinelli, A, Marinelli, SS, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, McEnery, J, Torres, E Mendoza, Mincer, AI, Miranda-Romagnoli, P, Moreno, E, Morgan, T, Mostafá, M, Nellen, L, Nemethy, P, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Ruiz-Velasco, E, Ryan, J, Salazar, H, Salesa, F, Sandoval, A, Parkinson, PM Saz, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, and Stump, D

Subjects
Primordial Black Holes, HAWC, Milagro, Very High Energy Bursts, astro-ph.HE, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

Primordial Black Holes (PBHs) are gravitationally collapsed objects that may have been created by density fluctuations in the early universe and could have arbitrarily small masses down to the Planck scale. Hawking showed that due to quantum effects, a black hole has a temperature inversely proportional to its mass and will emit all species of fundamental particles thermally. PBHs with initial masses of ∼5.0 × 1014 g should be expiring in the present epoch with bursts of high-energy particles, including gamma radiation in the GeV-TeV energy range. The Milagro high energy observatory, which operated from 2000 to 2008, is sensitive to the high end of the PBH evaporation gamma-ray spectrum. Due to its large field-of-view, more than 90% duty cycle and sensitivity up to 100 TeV gamma rays, the Milagro observatory is well suited to perform a search for PBH bursts. Based on a search on the Milagro data, we report new PBH burst rate density upper limits over a range of PBH observation times. In addition, we report the sensitivity of the Milagro successor, the High Altitude Water Cherenkov (HAWC) observatory, to PBH evaporation events.

Published
2015

53. VAMOS: A pathfinder for the HAWC gamma-ray observatory

Author

Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Ángeles, F, Arceo, R, Arteaga-Velázquez, JC, Avila-Aroche, A, Solares, HA Ayala, Badillo, C, Barber, AS, Baughman, BM, Bautista-Elivar, N, Gonzalez, J Becerra, Belmont, E, Benítez, E, BenZvi, SY, Berley, D, Bernal, A, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Cabrera, I, Carramiñana, A, Castañeda-Martínez, L, Castillo, M, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Diaz-Azuara, A, Diaz-Cruz, L, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, Dultzin, D, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, García-Torales, G, Garfias, F, González, A, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Guzmán-Cerón, C, Hampel-Arias, Z, Harding, JP, Hernández-Cervantes, L, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Langarica, R, Lara, A, Lara, G, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-Garcia, R, Marinelli, A, Martínez, LA, Martínez, H, Martínez, O, Martínez-Castro, J, Martos, M, Matthews, JAJ, McEnery, J, Torres, E Mendoza, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Page, DP, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Ramírez, I, Rentería, A, Rivière, C, and Rosa-González, D

Subjects
Detector prototype, Scientific verification, TeV cosmic rays, astro-ph.IM, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

VAMOS1 was a prototype detector built in 2011 at an altitude of 4100 m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.

Published
2015

54. The HAWC Gamma-Ray Observatory: Observations of Cosmic Rays

Author

HAWC Collaboration, Abeysekara, A. U., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., Arteaga-Velázquez, J. C., Solares, H. A. Ayala, Barber, A. S., Baughman, B. M., Bautista-Elivar, N., Belmont, E., BenZvi, S. Y., Berley, D., Rosales, M. Bonilla, Braun, J., Caballero-Lopez, R. A., Caballero-Mora, K. S., Carramiñana, A., Castillo, M., Cotti, U., Cotzomi, J., de la Fuente, E., De León, C., DeYoung, T., Hernandez, R. Diaz, Díaz-Vélez, J. C., Dingus, B. L., DuVernois, M. A., Ellsworth, R. W., Fernandez, A., Fiorino, D. W., Fraija, N., Galindo, A., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Hampel-Arias, Z., Hui, C. M., Hüntemeyer, P., Imran, A., Iriarte, A., Karn, P., Kieda, D., Kunde, G. J., Lara, A., Lauer, R. J., Lee, W. H., Lennarz, D., Vargas, H. León, Linares, E. C., Linnemann, J. T., Longo, M., Luna-GarcIa, R., Marinelli, A., Martinez, H., Martinez, O., Martínez-Castro, J., Matthews, J. A. J., Miranda-Romagnoli, P., Moreno, E., Mostafá, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Patricelli, B., Pelayo, R., Pérez-Pérez, E. G., Pretz, J., Rivière, C., Rosa-González, D., Salazar, H., Salesa, F., Sanchez, F. E., Sandoval, A., Santos, E., Schneider, M., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, R. W., Taboada, I., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Villaseñor, L., Weisgarber, T., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Younk, P. W., Zaborov, D., Zepeda, A., and Zhou, H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We describe measurements of GeV and TeV cosmic rays with the High-Altitude Water Cherenkov Gamma-Ray Observatory, or HAWC. The measurements include the observation of the shadow of the moon; the observation of small-scale and large-scale angular clustering of the TeV cosmic rays; the prospects for measurement of transient solar events with HAWC; and the observation of Forbush decreases with the HAWC engineering array and HAWC-30., Comment: Contributions to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 2013

Published
2013

55. The HAWC Gamma-Ray Observatory: Dark Matter, Cosmology, and Fundamental Physics

Author

HAWC Collaboration, Abeysekara, A. U., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., Arteaga-Velázquez, J. C., Solares, H. A. Ayala, Barber, A. S., Baughman, B. M., Bautista-Elivar, N., Belmont, E., BenZvi, S. Y., Berley, D., Rosales, M. Bonilla, Braun, J., Caballero-Lopez, R. A., Caballero-Mora, K. S., Carramiñana, A., Castillo, M., Cotti, U., Cotzomi, J., de la Fuente, E., De León, C., DeYoung, T., Hernandez, R. Diaz, Díaz-Vélez, J. C., Dingus, B. L., DuVernois, M. A., Ellsworth, R. W., Fernandez, A., Fiorino, D. W., Fraija, N., Galindo, A., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Hampel-Arias, Z., Hui, C. M., Hüntemeyer, P., Imran, A., Iriarte, A., Karn, P., Kieda, D., Kunde, G. J., Lara, A., Lauer, R. J., Lee, W. H., Lennarz, D., Vargas, H. León, Linares, E. C., Linnemann, J. T., Longo, M., Luna-GarcIa, R., Marinelli, A., Martinez, H., Martinez, O., Martínez-Castro, J., Matthews, J. A. J., Miranda-Romagnoli, P., Moreno, E., Mostafá, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Patricelli, B., Pelayo, R., Pérez-Pérez, E. G., Pretz, J., Rivière, C., Rosa-González, D., Salazar, H., Salesa, F., Sanchez, F. E., Sandoval, A., Santos, E., Schneider, M., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, R. W., Taboada, I., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Villaseñor, L., Weisgarber, T., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Younk, P. W., Zaborov, D., Zepeda, A., and Zhou, H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is designed to perform a synoptic survey of the TeV sky. The high energy coverage of the experiment will enable studies of fundamental physics beyond the Standard Model, and the large field of view of the detector will enable detailed studies of cosmologically significant backgrounds and magnetic fields. We describe the sensitivity of the full HAWC array to these phenomena in five contributions shown at the 33rd International Cosmic Ray Conference in Rio de Janeiro, Brazil (July 2013)., Comment: Contributions to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 2013

Published
2013

56. The HAWC Gamma-Ray Observatory: Design, Calibration, and Operation

Author

HAWC Collaboration, Abeysekara, A. U., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., Arteaga-Velázquez, J. C., Solares, H. A. Ayala, Barber, A. S., Baughman, B. M., Bautista-Elivar, N., Belmont, E., BenZvi, S. Y., Berley, D., Rosales, M. Bonilla, Braun, J., Caballero-Lopez, R. A., Caballero-Mora, K. S., Carramiñana, A., Castillo, M., Cotti, U., Cotzomi, J., de la Fuente, E., De León, C., DeYoung, T., Hernandez, R. Diaz, Díaz-Vélez, J. C., Dingus, B. L., DuVernois, M. A., Ellsworth, R. W., Fernandez, A., Fiorino, D. W., Fraija, N., Galindo, A., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Hampel-Arias, Z., Hui, C. M., Hüntemeyer, P., Imran, A., Iriarte, A., Karn, P., Kieda, D., Kunde, G. J., Lara, A., Lauer, R. J., Lee, W. H., Lennarz, D., Vargas, H. León, Linares, E. C., Linnemann, J. T., Longo, M., Luna-GarcIa, R., Marinelli, A., Martinez, H., Martinez, O., Martínez-Castro, J., Matthews, J. A. J., Miranda-Romagnoli, P., Moreno, E., Mostafá, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Patricelli, B., Pelayo, R., Pérez-Pérez, E. G., Pretz, J., Rivière, C., Rosa-González, D., Salazar, H., Salesa, F., Sanchez, F. E., Sandoval, A., Santos, E., Schneider, M., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, R. W., Taboada, I., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Villaseñor, L., Weisgarber, T., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Younk, P. W., Zaborov, D., Zepeda, A., and Zhou, H.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is under construction 4100 meters above sea level at Sierra Negra, Mexico. We describe the design and cabling of the detector, the characterization of the photomultipliers, and the timing calibration system. We also outline a next-generation detector based on the water Cherenkov technique., Comment: Contributions to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 2013

Published
2013

57. The HAWC Gamma-Ray Observatory: Sensitivity to Steady and Transient Sources of Gamma Rays

Author

HAWC Collaboration, Abeysekara, A. U., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., Arteaga-Velázquez, J. C., Solares, H. A. Ayala, Barber, A. S., Baughman, B. M., Bautista-Elivar, N., Belmont, E., BenZvi, S. Y., Berley, D., Rosales, M. Bonilla, Braun, J., Caballero-Lopez, R. A., Caballero-Mora, K. S., Carramiñana, A., Castillo, M., Cotti, U., Cotzomi, J., de la Fuente, E., De León, C., DeYoung, T., Hernandez, R. Diaz, Díaz-Vélez, J. C., Dingus, B. L., DuVernois, M. A., Ellsworth, R. W., Fernandez, A., Fiorino, D. W., Fraija, N., Galindo, A., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Hampel-Arias, Z., Hui, C. M., Hüntemeyer, P., Imran, A., Iriarte, A., Karn, P., Kieda, D., Kunde, G. J., Lara, A., Lauer, R. J., Lee, W. H., Lennarz, D., Vargas, H. León, Linares, E. C., Linnemann, J. T., Longo, M., Luna-GarcIa, R., Marinelli, A., Martinez, H., Martinez, O., Martínez-Castro, J., Matthews, J. A. J., Miranda-Romagnoli, P., Moreno, E., Mostafá, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Patricelli, B., Pelayo, R., Pérez-Pérez, E. G., Pretz, J., Rivière, C., Rosa-González, D., Salazar, H., Salesa, F., Sanchez, F. E., Sandoval, A., Santos, E., Schneider, M., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, R. W., Taboada, I., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Villaseñor, L., Weisgarber, T., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Younk, P. W., Zaborov, D., Zepeda, A., and Zhou, H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory is designed to record air showers produced by cosmic rays and gamma rays between 100 GeV and 100 TeV. Because of its large field of view and high livetime, HAWC is well-suited to measure gamma rays from extended sources, diffuse emission, and transient sources. We describe the sensitivity of HAWC to emission from the extended Cygnus region as well as other types of galactic diffuse emission; searches for flares from gamma-ray bursts and active galactic nuclei; and the first measurement of the Crab Nebula with HAWC-30., Comment: Contributions to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 2013

Published
2013

58. Sensitivity of the High Altitude Water Cherenkov Detector to Sources of Multi-TeV Gamma Rays

Author

Abeysekara, A. U., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., Arteaga-Velázquez, J. C., Solares, H. A. Ayala, Barber, A. S., Baughman, B. M., Bautista-Elivar, N., Belmont, E., BenZvi, S. Y., Berley, D., Rosales, M. Bonilla, Braun, J., Caballero-Lopez, R. A., Carramiñana, A., Castillo, M., Cotti, U., Cotzomi, J., de la Fuente, E., De León, C., DeYoung, T., Hernandez, R. Diaz, Diaz-Velez, J. C., Dingus, B. L., DuVernois, M. A., Ellsworth, R. W., Fernandez, A., Fiorino, D. W., Fraija, N., Galindo, A., Garcia-Luna, J. L., Garcia-Torales, G., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Hampel-Arias, Z., Hui, C. M., Hüntemeyer, P., Imran, A., Iriarte, A., Karn, P., Kieda, D., Kunde, G. J., Lara, A., Lauer, R. J., Lee, W. H., Lennarz, D., Vargas, H. León, Linares, E. C., Linnemann, J. T., Longo, M., Luna-García, R., Marinelli, A., Martinez, O., Martínez-Castro, J., Matthews, J. A. J., Miranda-Romagnoli, P., Moreno, E., Mostafá, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Patricelli, B., Pelayo, R., Pérez-Pérez, E. G., Pretz, J., Rivière, C., Rosa-González, D., Salazar, H., Salesa, F., Sandoval, A., Santos, E., Schneider, M., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, R. W., Taboada, I., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Villaseñor, L., Weisgarber, T., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Younk, P. W., Zaborov, D., Zepeda, A., and Zhou, H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The High Altitude Water Cherenkov (HAWC) observatory is an array of large water Cherenkov detectors sensitive to gamma rays and hadronic cosmic rays in the energy band between 100 GeV and 100 TeV. The observatory will be used to measure high-energy protons and cosmic rays via detection of the energetic secondary particles reaching the ground when one of these particles interacts in the atmosphere above the detector. HAWC is under construction at a site 4100 meters above sea level on the northern slope of the volcano Sierra Negra, which is located in central Mexico at 19 degrees N latitude. It is scheduled for completion in 2014. In this paper we estimate the sensitivity of the HAWC instrument to point-like and extended sources of gamma rays. The source fluxes are modeled using both unbroken power laws and power laws with exponential cutoffs. HAWC, in one year, is sensitive to point sources with integral power-law spectra as low as 5x10^-13 cm^-2 sec^-1 above 2 TeV (approximately 50 mCrab) over 5 sr of the sky. This is a conservative estimate based on simple event parameters and is expected to improve as the data analysis techniques are refined. We discuss known TeV sources and the scientific contributions that HAWC can make to our understanding of particle acceleration in these sources.

Published
2013
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61. On the sensitivity of the HAWC observatory to gamma-ray bursts

Author

HAWC collaboration, Abeysekara, A. U., Aguilar, J. A., Aguilar, S., Alfaro, R., Almaraz, E., Álvarez, C., Álvarez-Romero, J. de D., Álvarez, M., Arceo, R., Arteaga-Velázquez, J. C., Badillo, C., Barber, A., Baughman, B. M., Bautista-Elivar, N., Belmont, E., Benítez, E., BenZvi, S. Y., Berley, D., Bernal, A., Bonamente, E., Braun, J., Caballero-Lopez, R., Cabrera, I., Carramiñana, A., Carrasco, L., Castillo, M., Chambers, L., Conde, R., Condreay, P., Cotti, U., Cotzomi, J., D'Olivo, J. C., de la Fuente, E., De León, C., Delay, S., Delepine, D., DeYoung, T., Diaz, L., Diaz-Cruz, L., Dingus, B. L., Duvernois, M. A., Edmunds, D., Ellsworth, R. W., Fick, B., Fiorino, D. W., Flandes, A., Fraija, N. I., Galindo, A., García-Luna, J. L., García-Torales, G., Garfias, F., González, L. X., González, M. M., Goodman, J. A., Grabski, V., Gussert, M., Guzmán-Ceron, C., Hampel-Arias, Z., Harris, T., Hays, E., Hernandez-Cervantes, L., Hüntemeyer, P. H., Imran, A., Iriarte, A., Jimenez, J. J., Karn, P., Kelley-Hoskins, N., Kieda, D., Langarica, R., Lara, A., Lauer, R., Lee, W. H., Linares, E. C., Linnemann, J. T., Longo, M., Luna-García, R., Martínez, H., Martínez, J., Martínez, L. A., Martínez, O., Martínez-Castro, J., Martos, M., Matthews, J., McEnery, J. E., Medina-Tanco, G., Mendoza-Torres, J. E., Miranda-Romagnoli, P. A., Montaruli, T., Moreno, E., Mostafa, M., Napsuciale, M., Nava, J., Nellen, L., Newbold, M., Noriega-Papaqui, R., Oceguera-Becerra, T., Tapia, A. Olmos, Orozco, V., Pérez, V., Pérez-Pérez, E. G., Perkins, J. S., Pretz, J., Ramirez, C., Ramírez, I., Rebello, D., Rentería, A., Reyes, J., Rosa-González, D., Rosado, A., Ryan, J. M., Sacahui, J. R., Salazar, H., Salesa, F., Sandoval, A., Santos, E., Schneider, M., Shoup, A., Silich, S., Sinnis, G., Smith, A. J., Sparks, K., Springer, W., Suárez, F., Suarez, N., Taboada, I., Tellez, A. F., Tenorio-Tagle, G., Tepe, A., Toale, P. A., Tollefson, K., Torres, I., Ukwatta, T. N., Valdes-Galicia, J., Vanegas, P., Vasileiou, V., Vázquez, O., Vázquez, X., Villaseñor, L., Wall, W., Walters, J. S., Warner, D., Westerhoff, S., Wisher, I. G., Wood, J., Yodh, G. B., Zaborov, D., and Zepeda, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present the sensitivity of HAWC to Gamma Ray Bursts (GRBs). HAWC is a very high-energy gamma-ray observatory currently under construction in Mexico at an altitude of 4100 m. It will observe atmospheric air showers via the water Cherenkov method. HAWC will consist of 300 large water tanks instrumented with 4 photomultipliers each. HAWC has two data acquisition (DAQ) systems. The main DAQ system reads out coincident signals in the tanks and reconstructs the direction and energy of individual atmospheric showers. The scaler DAQ counts the hits in each photomultiplier tube (PMT) in the detector and searches for a statistical excess over the noise of all PMTs. We show that HAWC has a realistic opportunity to observe the high-energy power law components of GRBs that extend at least up to 30 GeV, as it has been observed by Fermi LAT. The two DAQ systems have an energy threshold that is low enough to observe events similar to GRB 090510 and GRB 090902b with the characteristics observed by Fermi LAT. HAWC will provide information about the high-energy spectra of GRBs which in turn could help to understanding about e-pair attenuation in GRB jets, extragalactic background light absorption, as well as establishing the highest energy to which GRBs accelerate particles.

Published
2011
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62. Quaternionic Darmon points on p-adic tori and abelian varieties

Author

Longo, M. and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Algebraic Geometry, 14G05, 11G10
Abstract

We prove formulas for the p-adic logarithm of quaternionic Darmon points on p-adic tori and modular abelian varieties over Q having purely multiplicative reduction at p. These formulas are amenable to explicit computations and are the first to treat Stark-Heegner type points on higher-dimensional abelian varieties., Comment: 16 pages

Published
2011

63. The rationality of quaternionic Darmon points over genus fields of real quadratic fields

Author

Longo, M. and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Algebraic Geometry, 14G05, 11G05
Abstract

Darmon points on p-adic tori and Jacobians of Shimura curves over Q were introduced in previous joint works with Rotger as generalizations of Darmon's Stark-Heegner points. In this article we study the algebraicity over extensions of a real quadratic field K of the projections of Darmon points to elliptic curves. More precisely, we prove that linear combinations of Darmon points on elliptic curves weighted by certain genus characters of K are rational over the predicted genus fields of K. This extends to an arbitrary quaternionic setting the main theorem on the rationality of Stark-Heegner points obtained by Bertolini and Darmon, and at the same time gives evidence for the rationality conjectures formulated in a joint paper with Rotger and by M. Greenberg in his article on Stark-Heegner points. In light of this result, quaternionic Darmon points represent the first instance of a systematic supply of points of Stark-Heegner type other than Darmon's original ones for which explicit rationality results are known., Comment: 34 pages

Published
2011

64. Forward Neutron Production at the Fermilab Main Injector

Author

Nigmanov, T. S., Rajaram, D., Longo, M. J., Akgun, U., Aydin, G., Baker, W., Barnes, Jr., P. D., Bergfeld, T., Bujak, A., Carey, D., Dukes, E. C., Duru, F., Feldman, G. J., Godley, A., Gülmez, E., Günaydin, Y. O., Graf, N., Gustafson, H. R., Gutay, L., Hartouni, E., Hanlet, P., Heffner, M., Johnstone, C., Kaplan, D. M., Kamaev, O., Klay, J., Kostin, M., Lange, D., Lebedev, A., Lu, L. C., Materniak, C., Messier, M. D., Meyer, H., Miller, D. E., Mishra, S. R., Nelson, K. S., Norman, A., Onel, Y., Paley, J. M., Park, H. K., Penzo, A., Peterson, R. J., Raja, R., Rosenfeld, C., Rubin, H. A., Seun, S., Solomey, N., Soltz, R., Swallow, E., Torun, Y., Wilson, K., Wright, D., and Wu, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We have measured cross sections for forward neutron production from a variety of targets using proton beams from the Fermilab Main Injector. Measurements were performed for proton beam momenta of 58 GeV/c, 84 GeV/c, and 120 GeV/c. The cross section dependence on the atomic weight (A) of the targets was found to vary as $A^(alpha)$ where $\alpha$ is $0.46\pm0.06$ for a beam momentum of 58 GeV/c and 0.54$\pm$0.05 for 120 GeV/c. The cross sections show reasonable agreement with FLUKA and DPMJET Monte Carlos. Comparisons have also been made with the LAQGSM Monte Carlo., Comment: Accepted for publication in Physical Review D. This version incorporates small changes suggested by referee and small corrections in the neutron production cross sections predicted by FLUKA

Published
2010
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65. Study of the rare hyperon decay Omega \to Xi \pi^+ \pi^-

Author

HyperCP Collaboration, Kamaev, O., Solomey, N., Burnstein, R. A., Chakravorty, A., Chen, Y. C., Choong, W. -S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gustafson, H. R., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T. D., Kaplan, D. M., Longo, M. J., Lu, L. C., Luebke, W., Luk, K. -B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rajaram, D., Rubin, H. A., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report a new measurement of the decay \Omega^- \to \Xi^- \pi^+ \pi^- with 76 events and a first observation of the decay \Omega^+ \to \Xi^+ \pi^+ \pi^- with 24 events, yielding a combined branching ratio (3.74 ^{+0.67}_{-0.56}) \times 10^{-4}. This represents a factor 25 increase in statistics over the best previous measurement. No evidence is seen for CP violation, with B(\Omega^- \to \Xi^- \pi^+ \pi^-)=4.04^{+0.83}_{-0.71} \times 10^{-4} and B(\Omega^+ \to \Xi^+ \pi^+ \pi^-)=3.15^{+1.12}_{-0.89} \times 10^{-4}. Contrary to theoretical expectation, we see little evidence for the decays \Omega^- \to \Xi_{1530}^{*0} \pi^- and \Omega^+ \to \Xi_{1530}^{*0} \pi^+ and place a 90% C.L. upper limit on the combined branching ratio B(\Omega^-(\Omega^+) \to \Xi^{*0}_{1530}(\Xi^{*0}_{1530}) \pi^\mp)<7.0 \times 10^{-5}., Comment: 6 pages, 5 figures, to be published in Phys. Lett. B

Published
2010
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66. An irreducibility criterion for group representations, with arithmetic applications

Author

Longo, M. and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Commutative Algebra, 20C12, 11F80
Abstract

We prove a criterion for the irreducibility of an integral group representation \rho over the fraction field of a noetherian domain R in terms of suitably defined reductions of \rho at prime ideals of R. As applications, we give irreducibility results for universal deformations of residual representations, with a special attention to universal deformations of residual Galois representations associated with modular forms of weight at least 2., Comment: 11 pages

Published
2010

67. SEARCH FOR GAMMA-RAYS FROM THE UNUSUALLY BRIGHT GRB 130427A WITH THE HAWC GAMMA-RAY OBSERVATORY

Author

Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, BenZvi, SY, Rosales, M Bonilla, Braun, J, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Hernandez, R Diaz, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, MM, Goodman, JA, Gussert, M, Hampel-Arias, Z, Harding, JP, Hüntemeyer, P, Hui, CM, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linnemann, JT, Longo, M, Luna-García, R, Malone, K, Marinelli, A, Marinelli, SS, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Torres, E Mendoza, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, TO, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Salazar, H, Greus, F Salesa, Sandoval, A, Schneider, M, Sinnis, G, Smith, AJ, Woodle, K Sparks, Springer, RW, Taboada, I, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, Zaborov, D, Zepeda, A, and Zhou, and H

Subjects
gamma-ray burst: individual, gamma rays: general, astro-ph.HE, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract

The first limits on the prompt emission from the long gamma-ray burst (GRB) 130427A in the >100 GeV energy band are reported. GRB 130427A was the most powerful burst ever detected with a redshift z ≲ 0.5 and featured the longest lasting emission above 100 MeV. The energy spectrum extends at least up to 95 GeV, clearly in the range observable by the High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory, a new extensive air shower detector currently under construction in central Mexico. The burst occurred under unfavorable observation conditions, low in the sky and when HAWC was running 10% of the final detector. Based on the observed light curve at MeV-GeV energies, eight different time periods have been searched for prompt and delayed emission from this GRB. In all cases, no statistically significant excess of counts has been found and upper limits have been placed. It is shown that a similar GRB close to zenith would be easily detected by the full HAWC detector, which will be completed soon. The detection rate of the full HAWC detector may be as high as one to two GRBs per year. A detection could provide important information regarding the high energy processes at work and the observation of a possible cut-off beyond the Fermi Large Area Telescope energy range could be the signature of gamma-ray absorption, either in the GRB or along the line of sight due to the extragalactic background light.

Published
2015

68. Hydrometeorological effects of historical land-conversion in an ecosystem-atmosphere model of Northern South America

Author

Knox, RG, Longo, M, Swann, ALS, Zhang, K, Levine, NM, Moorcroft, PR, and Bras, RL

Subjects
Physical Geography and Environmental Geoscience, Civil Engineering, Environmental Engineering
Abstract

This work investigates how the integrated land use of northern South America has affected the present day regional patterns of hydrology. A model of the terrestrial ecosystems (ecosystem demography model 2: ED2) is combined with an atmospheric model (Brazilian Regional Atmospheric Modeling System: BRAMS). Two realizations of the structure and composition of terrestrial vegetation are used as the sole differences in boundary conditions that drive two simulations. One realization captures the present day vegetation condition that includes deforestation and land conversion, the other is an estimate of the potential structure and composition of the region's vegetation without human influence. Model output is assessed for differences in resulting hydrometeorology. The simulations suggest that the history of land conversion in northern South America is not associated with a significant precipitation bias in the northern part of the continent, but has shown evidence of a negative bias in mean regional evapotranspiration and a positive bias in mean regional runoff. Also, negative anomalies in evaporation rates showed pattern similarity with areas where deforestation has occurred. In the central eastern Amazon there was an area where deforestation and abandonment had lead to an overall reduction of above-ground biomass, but this was accompanied by a shift in forest composition towards early successional functional types and grid-average-patterned increases in annual transpiration. Anomalies in annual precipitation showed mixed evidence of consistent patterning. Two focus areas were identified where more consistent precipitation anomalies formed, one in the Brazilian state of Pará where a dipole pattern formed, and one in the Bolivian Gran Chaco, where a negative anomaly was identified. These locations were scrutinized to understand the basis of their anomalous hydrometeorologic response. In both cases, deforestation led to increased total surface albedo, driving decreases in net radiation, boundary layer moist static energy and ultimately decreased convective precipitation. In the case of the Gran Chaco, decreased precipitation was also a result of decreased advective moisture transport, indicating that differences in local hydrometeorology may manifest via teleconnections with the greater region.

Published
2015

69. On rigid analytic uniformizations of Jacobians of Shimura curves

Author

Longo, M., Rotger, V., and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Algebraic Geometry, 14G35, 14G22
Abstract

The main goal of this article is to give an explicit rigid analytic uniformization of the maximal toric quotient of the Jacobian of a Shimura curve over the field of rational numbers at a prime dividing exactly the level. This result can be viewed as complementary to the classical theorem of Cerednik and Drinfeld which provides rigid analytic uniformizations at primes dividing the discriminant. As a corollary, we offer a proof of a conjecture formulated by M. Greenberg in his paper on Stark-Heegner points and quaternionic Shimura curves, thus making Greenberg's construction of local points on elliptic curves over the rationals unconditional., Comment: Corrected a few typos. Final version, to appear in American Journal of Mathematics

Published
2009

70. Searches for gravitational waves from known pulsars with S5 LIGO data

Author

The LIGO Scientific Collaboration, The Virgo Collaboration, Abbott, B. P., Abbott, R., Acernese, F., Adhikari, R., Ajith, P., Allen, B., Allen, G., Alshourbagy, M., Amin, R. S., Anderson, S. B., Anderson, W. G., Antonucci, F., Aoudia, S., Arain, M. A., Araya, M., Armandula, H., Armor, P., Arun, K. G., Aso, Y., Aston, S., Astone, P., Aufmuth, P., Aulbert, C., Babak, S., Baker, P., Ballardin, G., Ballmer, S., Barker, C., Barker, D., Barone, F., Barr, B., Barriga, P., Barsotti, L., Barsuglia, M., Barton, M. A., Bartos, I., Bassiri, R., Bastarrika, M., Bauer, Th. S., Behnke, B., Beker, M., Benacquista, M., Betzwieser, J., Beyersdorf, P. T., Bigotta, S., Bilenko, I. A., Billingsley, G., Birindelli, S., Biswas, R., Bizouard, M. A., Black, E., Blackburn, J. K., Blackburn, L., Blair, D., Bland, B., Boccara, C., Bodiya, T. P., Bogue, L., Bondu, F., Bonelli, L., Bork, R., Boschi, V., Bose, S., Bosi, L., Braccini, S., Bradaschia, C., Brady, P. R., Braginsky, V. B., Brau, J. E., Bridges, D. O., Brillet, A., Brinkmann, M., Brisson, V., Broeck, C. Van Den, Brooks, A. F., Brown, D. A., Brummit, A., Brunet, G., Budzynski, R., Bulik, T., Bullington, A., Bulten, H. J., Buonanno, A., Burmeister, O., Buskulic, D., Byer, R. L., Cadonati, L., Cagnoli, G., Calloni, E., Camp, J. B., Campagna, E., Cannizzo, J., Cannon, K. C., Canuel, B., Cao, J., Carbognani, F., Cardenas, L., Caride, S., Castaldi, G., Caudill, S., Cavaglià, M., Cavalier, F., Cavalieri, R., Cella, G., Cepeda, C., Cesarini, E., Chalermsongsak, T., Chalkley, E., Charlton, P., Chassande-Mottin, E., Chatterji, S., Chelkowski, S., Chen, Y., Chincarini, A., Christensen, N., Chung, C. T. Y., Clark, D., Clark, J., Clayton, J. H., Cleva, F., Coccia, E., Cokelaer, T., Colacino, C. N., Colas, J., Colla, A., Colombini, M., Conte, R., Cook, D., Corbitt, T. R. C., Corda, C., Cornish, N., Corsi, A., Coulon, J. -P., Coward, D., Coyne, D. C., Creighton, J. D. E., Creighton, T. D., Cruise, A. M., Culter, R. M., Cumming, A., Cunningham, L., Cuoco, E., Danilishin, S. L., D'Antonio, S., Danzmann, K., Dari, A., Dattilo, V., Daudert, B., Davier, M., Davies, G., Daw, E. J., Day, R., De Rosa, R., DeBra, D., Degallaix, J., del Prete, M., Dergachev, V., Desai, S., DeSalvo, R., Dhurandhar, S., Di Fiore, L., Di Lieto, A., Emilio, M. Di Paolo, Di Virgilio, A., Díaz, M., Dietz, A., Donovan, F., Dooley, K. L., Doomes, E. E., Drago, M., Drever, R. W. P., Dueck, J., Duke, I., Dumas, J. -C., Dwyer, J. G., Echols, C., Edgar, M., Effler, A., Ehrens, P., Espinoza, E., Etzel, T., Evans, M., Evans, T., Fafone, V., Fairhurst, S., Faltas, Y., Fan, Y., Fazi, D., Fehrmann, H., Ferrante, I., Fidecaro, F., Finn, L. S., Fiori, I., Flaminio, R., Flasch, K., Foley, S., Forrest, C., Fotopoulos, N., Fournier, J. -D., Franc, J., Franzen, A., Frasca, S., Frasconi, F., Frede, M., Frei, M., Frei, Z., Freise, A., Frey, R., Fricke, T., Fritschel, P., Frolov, V. V., Fyffe, M., Galdi, V., Gammaitoni, L., Garofoli, J. A., Garufi, F., Gemme, G., Genin, E., Gennai, A., Gholami, I., Giaime, J. A., Giampanis, S., Giardina, K. D., Giazotto, A., Goda, K., Goetz, E., Goggin, L. M., González, G., Gorodetsky, M. L., Goßler, S., Gouaty, R., Granata, M., Granata, V., Grant, A., Gras, S., Gray, C., Gray, M., Greenhalgh, R. J. S., Gretarsson, A. M., Greverie, C., Grimaldi, F., Grosso, R., Grote, H., Grunewald, S., Guenther, M., Guidi, G., Gustafson, E. K., Gustafson, R., Hage, B., Hallam, J. M., Hammer, D., Hammond, G. D., Hanna, C., Hanson, J., Harms, J., Harry, G. M., Harry, I. W., Harstad, E. D., Haughian, K., Hayama, K., Heefner, J., Heitmann, H., Hello, P., Heng, I. S., Heptonstall, A., Hewitson, M., Hild, S., Hirose, E., Hoak, D., Hodge, K. A., Holt, K., Hosken, D. J., Hough, J., Hoyland, D., Huet, D., Hughey, B., Huttner, S. H., Ingram, D. R., Isogai, T., Ito, M., Ivanov, A., Jaranowski, P., Johnson, B., Johnson, W. W., Jones, D. I., Jones, G., Jones, R., de la Jordana, L. Sancho, Ju, L., Kalmus, P., Kalogera, V., Kandhasamy, S., Kanner, J., Kasprzyk, D., Katsavounidis, E., Kawabe, K., Kawamura, S., Kawazoe, F., Kells, W., Keppel, D. G., Khalaidovski, A., Khalili, F. Y., Khan, R., Khazanov, E., King, P., Kissel, J. S., Klimenko, S., Kokeyama, K., Kondrashov, V., Kopparapu, R., Koranda, S., Kowalska, I., Kozak, D., Krishnan, B., Królak, A., Kumar, R., Kwee, P., La Penna, P., Lam, P. K., Landry, M., Lantz, B., Lazzarini, A., Lei, H., Lei, M., Leindecker, N., Leonor, I., Leroy, N., Letendre, N., Li, C., Lin, H., Lindquist, P. E., Littenberg, T. B., Lockerbie, N. A., Lodhia, D., Longo, M., Lorenzini, M., Loriette, V., Lormand, M., Losurdo, G., Lu, P., Lubinski, M., Lucianetti, A., Lück, H., Machenschalk, B., MacInnis, M., Mackowski, J. -M., Mageswaran, M., Mailand, K., Majorana, E., Man, N., Mandel, I., Mandic, V., Mantovani, M., Marchesoni, F., Marion, F., Márka, S., Márka, Z., Markosyan, A., Markowitz, J., Maros, E., Marque, J., Martelli, F., Martin, I. W., Martin, R. M., Marx, J. N., Mason, K., Masserot, A., Matichard, F., Matone, L., Matzner, R. A., Mavalvala, N., McCarthy, R., McClelland, D. E., McGuire, S. C., McHugh, M., McIntyre, G., McKechan, D. J. A., McKenzie, K., Mehmet, M., Melatos, A., Melissinos, A. C., Mendell, G., Menéndez, D. F., Menzinger, F., Mercer, R. A., Meshkov, S., Messenger, C., Meyer, M. S., Michel, C., Milano, L., Miller, J., Minelli, J., Minenkov, Y., Mino, Y., Mitrofanov, V. P., Mitselmakher, G., Mittleman, R., Miyakawa, O., Moe, B., Mohan, M., Mohanty, S. D., Mohapatra, S. R. P., Moreau, J., Moreno, G., Morgado, N., Morgia, A., Morioka, T., Mors, K., Mosca, S., Moscatelli, V., Mossavi, K., Mours, B., MowLowry, C., Mueller, G., Muhammad, D., Mühlen, H. zur, Mukherjee, S., Mukhopadhyay, H., Mullavey, A., Müller-Ebhardt, H., Munch, J., Murray, P. G., Myers, E., Myers, J., Nash, T., Nelson, J., Neri, I., Newton, G., Nishizawa, A., Nocera, F., Numata, K., Ochsner, E., O'Dell, J., Ogin, G. H., O'Reilly, B., O'Shaughnessy, R., Ottaway, D. J., Ottens, R. S., Overmier, H., Owen, B. J., Pagliaroli, G., Palomba, C., Pan, Y., Pankow, C., Paoletti, F., Papa, M. A., Parameshwaraiah, V., Pardi, S., Pasqualetti, A., Passaquieti, R., Passuello, D., Patel, P., Pedraza, M., Penn, S., Perreca, A., Persichetti, G., Pichot, M., Piergiovanni, F., Pierro, V., Pietka, M., Pinard, L., Pinto, I. M., Pitkin, M., Pletsch, H. J., Plissi, M. V., Poggiani, R., Postiglione, F., Prato, M., Principe, M., Prix, R., Prodi, G. A., Prokhorov, L., Puncken, O., Punturo, M., Puppo, P., Quetschke, V., Raab, F. J., Rabaste, O., Rabeling, D. S., Radkins, H., Raffai, P., Raics, Z., Rainer, N., Rakhmanov, M., Rapagnani, P., Raymond, V., Re, V., Reed, C. M., Reed, T., Regimbau, T., Rehbein, H., Reid, S., Reitze, D. H., Ricci, F., Riesen, R., Riles, K., Rivera, B., Roberts, P., Robertson, N. A., Robinet, F., Robinson, C., Robinson, E. L., Rocchi, A., Roddy, S., Rolland, L., Rollins, J., Romano, J. D., Romano, R., Romie, J. H., Rosinska, D., Röver, C., Rowan, S., Rüdiger, A., Ruggi, P., Russell, P., Ryan, K., Sakata, S., Salemi, F., Sandberg, V., Sannibale, V., Santamaría, L., Saraf, S., Sarin, P., Sassolas, B., Sathyaprakash, B. S., Sato, S., Satterthwaite, M., Saulson, P. R., Savage, R., Savov, P., Scanlan, M., Schilling, R., Schnabel, R., Schofield, R., Schulz, B., Schutz, B. F., Schwinberg, P., Scott, J., Scott, S. M., Searle, A. C., Sears, B., Seifert, F., Sellers, D., Sengupta, A. S., Sentenac, D., Sergeev, A., Shapiro, B., Shawhan, P., Shoemaker, D. H., Sibley, A., Siemens, X., Sigg, D., Sinha, S., Sintes, A. M., Slagmolen, B. J. J., Slutsky, J., van der Sluys, M. V., Smith, J. R., Smith, M. R., Smith, N. D., Somiya, K., Sorazu, B., Stein, A., Stein, L. C., Steplewski, S., Stochino, A., Stone, R., Strain, K. A., Strigin, S., Stroeer, A., Sturani, R., Stuver, A. L., Summerscales, T. Z., Sun, K. -X., Sung, M., Sutton, P. J., Swinkels, B., Szokoly, G. P., Talukder, D., Tang, L., Tanner, D. B., Tarabrin, S. P., Taylor, J. R., Taylor, R., Terenzi, R., Thacker, J., Thorne, K. A., Thorne, K. S., Thüring, A., Tokmakov, K. V., Toncelli, A., Tonelli, M., Torres, C., Torrie, C., Tournefier, E., Travasso, F., Traylor, G., Trias, M., Trummer, J., Ugolini, D., Ulmen, J., Urbanek, K., Vahlbruch, H., Vajente, G., Vallisneri, M., Brand, J. F. J. van den, van der Putten, S., Vass, S., Vaulin, R., Vavoulidis, M., Vecchio, A., Vedovato, G., van Veggel, A. A., Veitch, J., Veitch, P., Veltkamp, C., Verkindt, D., Vetrano, F., Viceré, A., Villar, A., Vinet, J. -Y., Vocca, H., Vorvick, C., Vyachanin, S. P., Waldman, S. J., Wallace, L., Ward, R. L., Was, M., Weidner, A., Weinert, M., Weinstein, A. J., Weiss, R., Wen, L., Wen, S., Wette, K., Whelan, J. T., Whitcomb, S. E., Whiting, B. F., Wilkinson, C., Willems, P. A., Williams, H. R., Williams, L., Willke, B., Wilmut, I., Winkelmann, L., Winkler, W., Wipf, C. C., Wiseman, A. G., Woan, G., Wooley, R., Worden, J., Wu, W., Yakushin, I., Yamamoto, H., Yan, Z., Yoshida, S., Yvert, M., Zanolin, M., Zhang, J., Zhang, L., Zhao, C., Zotov, N., Zucker, M. E., Zweizig, J., Bégin, S., Corongiu, A., D'Amico, N., Freire, P. C. C., Hessels, J. W. T., Hobbs, G. B., Kramer, M., Lyne, A. G., Manchester, R. N., Marshall, F. E., Middleditch, J., Possenti, A., Ransom, S. M., Stairs, I. H., and Stappers, B.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Galaxy Astrophysics, General Relativity and Quantum Cosmology
Abstract

We present a search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors. For this search ephemerides overlapping the run period were obtained for all pulsars using radio and X-ray observations. We demonstrate an updated search method that allows for small uncertainties in the pulsar phase parameters to be included in the search. We report no signal detection from any of the targets and therefore interpret our results as upper limits on the gravitational wave signal strength. The most interesting limits are those for young pulsars. We present updated limits on gravitational radiation from the Crab pulsar, where the measured limit is now a factor of seven below the spin-down limit. This limits the power radiated via gravitational waves to be less than ~2% of the available spin-down power. For the X-ray pulsar J0537-6910 we reach the spin-down limit under the assumption that any gravitational wave signal from it stays phase locked to the X-ray pulses over timing glitches, and for pulsars J1913+1011 and J1952+3252 we are only a factor of a few above the spin-down limit. Of the recycled millisecond pulsars several of the measured upper limits are only about an order of magnitude above their spin-down limits. For these our best (lowest) upper limit on gravitational wave amplitude is 2.3x10^-26 for J1603-7202 and our best (lowest) limit on the inferred pulsar ellipticity is 7.0x10^-8 for J2124-3358., Comment: 39 pages, 5 figures, Accepted in The Astrophysical Journal

Published
2009
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71. Charged Kaon Mass Measurement using the Cherenkov Effect

Author

The MIPP Collaboration, Graf, N., Lebedev, A., Abrams, R. J., Akgun, U., Aydin, G., Baker, W., Barnes Jr., P. D., Bergfeld, T., Beverly, L., Bujak, A., Carey, D., Dukes, C., Duru, F., Feldman, G. J., Godley, A., Gülmez, E., Günaydın, Y. O., Gustafson, H. R., Gutay, L., Hartouni, E., Hanlet, P., Hansen, S., Heffner, M., Johnstone, C., Kaplan, D., Kamaev, O., Kilmer, J., Klay, J., Kostin, M., Lange, D., Ling, J., Longo, M. J., Lu, L. C., Materniak, C., Messier, M. D., Meyer, H., Miller, D. E., Mishra, S. R., Nelson, K., Nigmanov, T., Norman, A., Onel, Y., Paley, J. M., Park, H. K., Penzo, A., Peterson, R. J., Raja, R., Rajaram, D., Ratnikov, D., Rosenfeld, C., Rubin, H., Seun, S., Solomey, N., Soltz, R., Swallow, E., Schmitt, R., Subbarao, P., Torun, Y., Tope, T. E., Wilson, K., Wright, D., and Wu, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 ppm and 22 ppm yet differ from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 GeV/c to +63 GeV/c. The measured value is 491.3 +/- 1.7 MeV/c^2, which is within 1.4 sigma of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment., Comment: 6 pages, 7 figures. Submitted to Nuclear Instruments and Methods A

Published
2009
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72. Search for gravitational-wave bursts associated with gamma-ray bursts using data from LIGO Science Run 5 and Virgo Science Run 1

Author

LIGO Scientific Collaboration, Virgo Collaboration, Abbott, B. P., Abbott, R., Acernese, F., Adhikari, R., Ajith, P., Allen, B., Allen, G., Alshourbagy, M., Amin, R. S., Anderson, S. B., Anderson, W. G., Antonucci, F., Aoudia, S., Arain, M. A., Araya, M., Armandula, H., Armor, P., Arun, K. G., Aso, Y., Aston, S., Astone, P., Aufmuth, P., Aulbert, C., Babak, S., Baker, P., Ballardin, G., Ballmer, S., Barker, C., Barker, D., Barone, F., Barr, B., Barriga, P., Barsotti, L., Barsuglia, M., Barton, M. A., Bartos, I., Bassiri, R., Bastarrika, M., Bauer, Th. S., Behnke, B., Beker, M., Benacquista, M., Betzwieser, J., Beyersdorf, P. T., Bigotta, S., Bilenko, I. A., Billingsley, G., Birindelli, S., Biswas, R., Bizouard, M. A., Black, E., Blackburn, J. K., Blackburn, L., Blair, D., Bland, B., Boccara, C., Bodiya, T. P., Bogue, L., Bondu, F., Bonelli, L., Bork, R., Boschi, V., Bose, S., Bosi, L., Braccini, S., Bradaschia, C., Brady, P. R., Braginsky, V. B., Brau, J. E., Bridges, D. O., Brillet, A., Brinkmann, M., Brisson, V., Broeck, C. Van Den, Brooks, A. F., Brown, D. A., Brummit, A., Brunet, G., Budzyński, R., Bulik, T., Bullington, A., Bulten, H. J., Buonanno, A., Burmeister, O., Buskulic, D., Byer, R. L., Cadonati, L., Cagnoli, G., Calloni, E., Camp, J. B., Campagna, E., Cannizzo, J., Cannon, K. C., Canuel, B., Cao, J., Carbognani, F., Cardenas, L., Caride, S., Castaldi, G., Caudill, S., Cavaglià, M., Cavalier, F., Cavalieri, R., Cella, G., Cepeda, C., Cesarini, E., Chalermsongsak, T., Chalkley, E., Charlton, P., Chassande-Mottin, E., Chatterji, S., Chelkowski, S., Chen, Y., Chincarini, A., Christensen, N., Chung, C. T. Y., Clark, D., Clark, J., Clayton, J. H., Cleva, F., Coccia, E., Cokelaer, T., Colacino, C. N., Colas, J., Colla, A., Colombini, M., Conte, R., Cook, D., Corbitt, T. R. C., Corda, C., Cornish, N., Corsi, A., Coulon, J. -P., Coward, D., Coyne, D. C., Creighton, J. D. E., Creighton, T. D., Cruise, A. M., Culter, R. M., Cumming, A., Cunningham, L., Cuoco, E., Danilishin, S. L., D'Antonio, S., Danzmann, K., Dari, A., Dattilo, V., Daudert, B., Davier, M., Davies, G., Daw, E. J., Day, R., De Rosa, R., DeBra, D., Degallaix, J., del Prete, M., Dergachev, V., Desai, S., DeSalvo, R., Dhurandhar, S., Di Fiore, L., Di Lieto, A., Emilio, M. Di Paolo, Di Virgilio, A., Díaz, M., Dietz, A., Donovan, F., Dooley, K. L., Doomes, E. E., Drago, M., Drever, R. W. P., Dueck, J., Duke, I., Dumas, J. -C., Dwyer, J. G., Echols, C., Edgar, M., Edwards, M., Effler, A., Ehrens, P., Espinoza, E., Etzel, T., Evans, M., Evans, T., Fafone, V., Fairhurst, S., Faltas, Y., Fan, Y., Fazi, D., Fehrmann, H., Ferrante, I., Fidecaro, F., Finn, L. S., Fiori, I., Flaminio, R., Flasch, K., Foley, S., Forrest, C., Fotopoulos, N., Fournier, J. -D., Franc, J., Franzen, A., Frasca, S., Frasconi, F., Frede, M., Frei, M., Frei, Z., Freise, A., Frey, R., Fricke, T., Fritschel, P., Frolov, V. V., Fyffe, M., Galdi, V., Gammaitoni, L., Garofoli, J. A., Garufi, F., Gemme, G., Genin, E., Gennai, A., Gholami, I., Giaime, J. A., Giampanis, S., Giardina, K. D., Giazotto, A., Goda, K., Goetz, E., Goggin, L. M., González, G., Gorodetsky, M. L., Goeßzetler, S., Goßler, S., Gouaty, R., Granata, M., Granata, V., Grant, A., Gras, S., Gray, C., Gray, M., Greenhalgh, R. J. S., Gretarsson, A. M., Greverie, C., Grimaldi, F., Grosso, R., Grote, H., Grunewald, S., Guenther, M., Guidi, G., Gustafson, E. K., Gustafson, R., Hage, B., Hallam, J. M., Hammer, D., Hammond, G. D., Hanna, C., Hanson, J., Harms, J., Harry, G. M., Harry, I. W., Harstad, E. D., Haughian, K., Hayama, K., Heefner, J., Heitmann, H., Hello, P., Heng, I. S., Heptonstall, A., Hewitson, M., Hild, S., Hirose, E., Hoak, D., Hodge, K. A., Holt, K., Hosken, D. J., Hough, J., Hoyland, D., Huet, D., Hughey, B., Huttner, S. H., Ingram, D. R., Isogai, T., Ito, M., Ivanov, A., Jaranowski, P., Johnson, B., Johnson, W. W., Jones, D. I., Jones, G., Jones, R., de la Jordana, L. Sancho, Ju, L., Kalmus, P., Kalogera, V., Kandhasamy, S., Kanner, J., Kasprzyk, D., Katsavounidis, E., Kawabe, K., Kawamura, S., Kawazoe, F., Kells, W., Keppel, D. G., Khalaidovski, A., Khalili, F. Y., Khan, R., Khazanov, E., King, P., Kissel, J. S., Klimenko, S., Kokeyama, K., Kondrashov, V., Kopparapu, R., Koranda, S., Kowalska, I., Kozak, D., Krishnan, B., Królak, A., Kumar, R., Kwee, P., La Penna, P., Lam, P. K., Landry, M., Lantz, B., Lazzarini, A., Lei, H., Lei, M., Leindecker, N., Leonor, I., Leroy, N., Letendre, N., Li, C., Lin, H., Lindquist, P. E., Littenberg, T. B., Lockerbie, N. A., Lodhia, D., Longo, M., Lorenzini, M., Loriette, V., Lormand, M., Losurdo, G., Lu, P., Lubinski, M., Lucianetti, A., Lück, H., Machenschalk, B., MacInnis, M., Mackowski, J. -M., Mageswaran, M., Mailand, K., Majorana, E., Man, N., Mandel, I., Mandic, V., Mantovani, M., Marchesoni, F., Marion, F., Márka, S., Márka, Z., Markosyan, A., Markowitz, J., Maros, E., Marque, J., Martelli, F., Martin, I. W., Martin, R. M., Marx, J. N., Mason, K., Masserot, A., Matichard, F., Matone, L., Matzner, R. A., Mavalvala, N., McCarthy, R., McClelland, D. E., McGuire, S. C., McHugh, M., McIntyre, G., McKechan, D. J. A., McKenzie, K., Mehmet, M., Melatos, A., Melissinos, A. C., Mendell, G., Menéndez, D. F., Menzinger, F., Mercer, R. A., Meshkov, S., Messenger, C., Meyer, M. S., Michel, C., Milano, L., Miller, J., Minelli, J., Minenkov, Y., Mino, Y., Mitrofanov, V. P., Mitselmakher, G., Mittleman, R., Miyakawa, O., Moe, B., Mohan, M., Mohanty, S. D., Mohapatra, S. R. P., Moreau, J., Moreno, G., Morgado, N., Morgia, A., Morioka, T., Mors, K., Mosca, S., Moscatelli, V., Mossavi, K., Mours, B., MowLowry, C., Mueller, G., Muhammad, D., Mühlen, H. zur, Mukherjee, S., Mukhopadhyay, H., Mullavey, A., Müller-Ebhardt, H., Munch, J., Murray, P. G., Myers, E., Myers, J., Nash, T., Nelson, J., Neri, I., Newton, G., Nishizawa, A., Nocera, F., Numata, K., Ochsner, E., O'Dell, J., Ogin, G. H., O'Reilly, B., O'Shaughnessy, R., Ottaway, D. J., Ottens, R. S., Overmier, H., Owen, B. J., Pagliaroli, G., Palomba, C., Pan, Y., Pankow, C., Paoletti, F., Papa, M. A., Parameshwaraiah, V., Pardi, S., Pasqualetti, A., Passaquieti, R., Passuello, D., Patel, P., Pedraza, M., Penn, S., Perreca, A., Persichetti, G., Pichot, M., Piergiovanni, F., Pierro, V., Pietka, M., Pinard, L., Pinto, I. M., Pitkin, M., Pletsch, H. J., Plissi, M. V., Poggiani, R., Postiglione, F., Prato, M., Principe, M., Prix, R., Prodi, G. A., Prokhorov, L., Punken, O., Punturo, M., Puppo, P., Quetschke, V., Raab, F. J., Rabaste, O., Rabeling, D. S., Radkins, H., Raffai, P., Raics, Z., Rainer, N., Rakhmanov, M., Rapagnani, P., Raymond, V., Re, V., Reed, C. M., Reed, T., Regimbau, T., Rehbein, H., Reid, S., Reitze, D. H., Ricci, F., Riesen, R., Riles, K., Rivera, B., Roberts, P., Robertson, N. A., Robinet, F., Robinson, C., Robinson, E. L., Rocchi, A., Roddy, S., Rolland, L., Rollins, J., Romano, J. D., Romano, R., Romie, J. H., Rosińska, D., Röver, C., Rowan, S., Rüdiger, A., Ruggi, P., Russell, P., Ryan, K., Sakata, S., Salemi, F., Sandberg, V., Sannibale, V., Santamaría, L., Saraf, S., Sarin, P., Sassolas, B., Sathyaprakash, B. S., Sato, S., Satterthwaite, M., Saulson, P. R., Savage, R., Savov, P., Scanlan, M., Schilling, R., Schnabel, R., Schofield, R., Schulz, B., Schutz, B. F., Schwinberg, P., Scott, J., Scott, S. M., Searle, A. C., Sears, B., Seifert, F., Sellers, D., Sengupta, A. S., Sentenac, D., Sergeev, A., Shapiro, B., Shawhan, P., Shoemaker, D. H., Sibley, A., Siemens, X., Sigg, D., Sinha, S., Sintes, A. M., Slagmolen, B. J. J., Slutsky, J., van der Sluys, M. V., Smith, J. R., Smith, M. R., Smith, N. D., Somiya, K., Sorazu, B., Stein, A., Stein, L. C., Steplewski, S., Stochino, A., Stone, R., Strain, K. A., Strigin, S., Stroeer, A., Sturani, R., Stuver, A. L., Summerscales, T. Z., Sun, K. -X., Sung, M., Sutton, Patrick J., Swinkels, B., Szokoly, G. P., Talukder, D., Tang, L., Tanner, D. B., Tarabrin, S. P., Taylor, J. R., Taylor, R., Terenzi, R., Thacker, J., Thorne, K. A., Thorne, K. S., Thüring, A., Tokmakov, K. V., Toncelli, A., Tonelli, M., Torres, C., Torrie, C., Tournefier, E., Travasso, F., Traylor, G., Trias, M., Trummer, J., Ugolini, D., Ulmen, J., Urbanek, K., Vahlbruch, H., Vajente, G., Vallisneri, M., Brand, J. F. J. van den, van der Putten, S., Vass, S., Vaulin, R., Vavoulidis, M., Vecchio, A., Vedovato, G., van Veggel, A. A., Veitch, J., Veitch, P., Veltkamp, C., Verkindt, D., Vetrano, F., Viceré, A., Villar, A., Vinet, J. -Y., Vocca, H., Vorvick, C., Vyachanin, S. P., Waldman, S. J., Wallace, L., Ward, R. L., Was, M., Weidner, A., Weinert, M., Weinstein, A. J., Weiss, R., Wen, L., Wen, S., Wette, K., Whelan, J. T., Whitcomb, S. E., Whiting, B. F., Wilkinson, C., Willems, P. A., Williams, H. R., Williams, L., Willke, B., Wilmut, I., Winkelmann, L., Winkler, W., Wipf, C. C., Wiseman, A. G., Woan, G., Wooley, R., Worden, J., Wu, W., Yakushin, I., Yamamoto, H., Yan, Z., Yoshida, S., Yvert, M., Zanolin, M., Zhang, J., Zhang, L., Zhao, C., Zotov, N., Zucker, M. E., and Zweizig, J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology
Abstract

We present the results of a search for gravitational-wave bursts associated with 137 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments during the fifth LIGO science run and first Virgo science run. The data used in this analysis were collected from 2005 November 4 to 2007 October 1, and most of the GRB triggers were from the Swift satellite. The search uses a coherent network analysis method that takes into account the different locations and orientations of the interferometers at the three LIGO-Virgo sites. We find no evidence for gravitational-wave burst signals associated with this sample of GRBs. Using simulated short-duration (<1 s) waveforms, we set upper limits on the amplitude of gravitational waves associated with each GRB. We also place lower bounds on the distance to each GRB under the assumption of a fixed energy emission in gravitational waves, with typical limits of D ~ 15 Mpc (E_GW^iso / 0.01 M_o c^2)^1/2 for emission at frequencies around 150 Hz, where the LIGO-Virgo detector network has best sensitivity. We present astrophysical interpretations and implications of these results, and prospects for corresponding searches during future LIGO-Virgo runs., Comment: 16 pages, 3 figures. Updated references. To appear in ApJ.

Published
2009
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73. Quaternion algebras, Heegner points and the arithmetic of Hida families

Author

Longo, M. and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Algebraic Geometry, 11F11, 11R23
Abstract

Given a newform f, we extend Howard's results on the variation of Heegner points in the Hida family of f to a general quaternionic setting. More precisely, we build big Heegner points and big Heegner classes in terms of compatible families of Heegner points on towers of Shimura curves. The novelty of our approach, which systematically exploits the theory of optimal embeddings, consists in treating both the case of definite quaternion algebras and the case of indefinite quaternion algebras in a uniform way. We prove results on the size of Nekov\'a\v{r}'s extended Selmer groups attached to suitable big Galois representations and we formulate two-variable Iwasawa main conjectures both in the definite case and in the indefinite case. Moreover, in the definite case we propose refined conjectures \`a la Greenberg on the vanishing at the critical points of (twists of) the L-functions of the modular forms in the Hida family of f living on the same branch as f., Comment: Heavily revised and shortened version, to appear in Manuscripta Mathematica

Published
2009

74. Electromagnetic and Hadron Calorimeters in the MIPP Experiment

Author

Nigmanov, T. S., Gustafson, H. R., Longo, M. J., Park, H. K., Rajaram, D., Dukes, C., Lu, L. C., Materniak, C., Nelson, K., Norman, A., Meyer, H., Lebedev, A., Seun, S., Graf, N., Paley, J. M., Aydin, G., Gunaydin, Y., and Miller, D. E.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons and nucleons in pi, K and p interactions on various targets using beams from the Main Injector at Fermilab. The function of the calorimeters is to measure the production of forward-going neutrons and photons. The electromagnetic calorimeter consist of 10 lead plates interspersed with proportional chambers. It was followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. The data presented were collected with a variety of targets and beam momenta from 5 GeV/c to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons, and protons is discussed. The resolution for electrons was found to be 0.27/sqrt(E), and for hadrons the resolution was 0.554/sqrt(E) with a constant term of 2.6%. The performance of the calorimeters was tested on a neutron sample.

Published
2009
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76. Sensitivity of HAWC to high-mass dark matter annihilations

Author

Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Gonzalez, J Becerra, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Hernandez, R Diaz, Diaz-Cruz, L, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Harding, JP, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-Garcia, R, Marinelli, A, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, McEnery, J, Torres, E Mendoza, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Ryan, J, Salazar, H, Salesa, F, Sanchez, FE, Sandoval, A, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Woodle, K Sparks, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, and Younk, PW

Subjects
astro-ph.HE, astro-ph.CO, hep-ph, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics
Abstract

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in central Mexico at 19° North latitude and 4100 m above sea level, HAWC will observe gamma rays and cosmic rays with an array of water Cherenkov detectors. The full HAWC array is scheduled to be operational in Spring 2015. In this paper, we study the HAWC sensitivity to the gamma-ray signatures of high-mass (multi-TeV) dark matter annihilation. The HAWC observatory will be sensitive to diverse searches for dark matter annihilation, including annihilation from extended dark matter sources, the diffuse gamma-ray emission from dark matter annihilation, and gamma-ray emission from nonluminous dark matter subhalos. Here we consider the HAWC sensitivity to a subset of these sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the Galactic center. We simulate the HAWC response to gamma rays from these sources in several well-motivated dark matter annihilation channels. If no gamma-ray excess is observed, we show the limits HAWC can place on the dark matter cross section from these sources. In particular, in the case of dark matter annihilation into gauge bosons, HAWC will be able to detect a narrow range of dark matter masses to cross sections below thermal. HAWC should also be sensitive to nonthermal cross sections for masses up to nearly 1000 TeV. The constraints placed by HAWC on the dark matter cross section from known sources should be competitive with current limits in the mass range where HAWC has similar sensitivity. HAWC can additionally explore higher dark matter masses than are currently constrained.

Published
2014

77. OBSERVATION OF SMALL-SCALE ANISOTROPY IN THE ARRIVAL DIRECTION DISTRIBUTION OF TeV COSMIC RAYS WITH HAWC

Author

Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, MM, Goodman, JA, Gussert, M, Hampel-Arias, Z, Harding, JP, Hüntemeyer, P, Hui, CM, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linnemann, JT, Longo, M, Luna-García, R, Malone, K, Marinelli, A, Marinelli, SS, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, McEnery, J, Torres, E Mendoza, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Ruiz-Velasco, E, Ryan, J, Salazar, H, Greus, F Salesa, Sandoval, A, Schneider, M, Sinnis, G, Smith, AJ, Woodle, K Sparks, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, Zaborov, D, Zepeda, A, and Zhou, and H

Subjects
Astroparticle physics, Cosmic rays, astroparticle physics, cosmic rays, astro-ph.HE, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract

The High-Altitude Water Cherenkov (HAWC) Observatory is sensitive to gamma rays and charged cosmic rays at TeV energies. The detector is still under construction, but data acquisition with the partially deployed detector started in 2013. An analysis of the cosmic-ray arrival direction distribution based on 4.9 × 1010 events recorded between 2013 June and 2014 February shows anisotropy at the 10-4 level on angular scales of about 10°. The HAWC cosmic-ray sky map exhibits three regions of significantly enhanced cosmic-ray flux; two of these regions were first reported by the Milagro experiment. A third region coincides with an excess recently reported by the ARGO-YBJ experiment. An angular power spectrum analysis of the sky shows that all terms up to l = 15 contribute significantly to the excesses.

Published
2014

78. On the vanishing of Selmer groups for elliptic curves over ring class fields

Author

Longo, M. and Vigni, S.

Subjects
Mathematics - Number Theory, Mathematics - Algebraic Geometry, 11G05, 11G40
Abstract

Let E be a rational elliptic curve of conductor N without complex multiplication and let K be an imaginary quadratic field of discriminant D prime to N. Assume that the number of primes dividing N and inert in K is odd, and let H be the ring class field of K of conductor c prime to ND with Galois group G over K. Fix a complex character \chi of G. Our main result is that if the special value of the \chi-twisted L-function of E/K is non-zero then the tensor product (with respect to \chi) of the p-Selmer group of E/H with W over Z[G] is 0 for all but finitely many primes p, where W is a suitable finite extension of Z_p containing the values of \chi. Our work extends results of Bertolini and Darmon to almost all non-ordinary primes p and also offers alternative proofs of a \chi-twisted version of the Birch and Swinnerton-Dyer conjecture for E over H (Bertolini and Darmon) and of the vanishing of the p-Selmer group of E/K for almost all p (Kolyvagin) in the case of analytic rank zero., Comment: 31 pages, minor modifications; final version, to appear in Journal of Number Theory

Published
2008

80. Search for the Lepton-Number-Violating Decay $\Xi^- \to p \mu^- \mu^-$

Author

HyperCP Collaboration, Rajaram, D., Burnstein, R. A., Chakravorty, A., Chen, Y. C., Choong, W. -S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gustafson, H. R., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T. D., Kaplan, D. M., Longo, M. J., Lu, L. C., Luebke, W., Luk, K. -B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rubin, H. A., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

A sensitive search for the lepton-number-violating decay $\Xi^-\to p \mu^-\mu^-$ has been performed using a sample of $\sim10^9$ $\Xi^-$ hyperons produced in 800 GeV/$c$ $p$-Cu collisions. We obtain $\mathcal{B}(\Xi^-\to p \mu^-\mu^-)< 4.0\times 10^{-8}$ at 90% confidence, improving on the best previous limit by four orders of magnitude., Comment: 9 pages, 5 figures, to be published in Phys. Rev. Lett

Published
2005
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81. Observation of Parity Violation in the Omega-minus -> Lambda + K-minus Decay

Author

HyperCP Collaboration, Lu, L. C., Burnstein, R. A., Chakravorty, A., Chen, Y. C., Choong, W. -S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gustafson, H. R., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T. D., Kaplan, D. M., Longo, M. J., Luebke, W., Luk, K. -B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rajaram, D., Rubin, H. A., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

The alpha decay parameter in the process Omega-minus -> Lambda + K-minus has been measured from a sample of 4.50 million unpolarized Omega-minus decays recorded by the HyperCP (E871) experiment at Fermilab and found to be [1.78 +/- 0.19(stat) +/- 0.16(syst)]{\times}10^{-2}. This is the first unambiguous evidence for a nonzero alpha decay parameter, and hence parity violation, in the Omega-minus -> Lambda + K-minus decay., Comment: 10 pages, 7 figures

Published
2005
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82. delta S = 2 nonleptonic hyperon decays

Author

White, C. G., Burnstein, R. A., Chakravorty, A., Chan, A., Chen, Y. C., Choong, W. S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Gidal, G., Gu, P., Gustafson, H. R., Ho, C., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Kaplan, D. M., Lederman, L. M., Leros, N., Longo, M. J., Lopez, F., Lu, L. C., Luebke, W., Luk, K. B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rajaram, D., Rubin, H. A., Teng, P. K., Volk, J., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

A sensitive search for the rare decays \Omega^- \to \Lambda \pi^- and \Xi^0 \to p \pi^- has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |\Delta S| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(\Omega^- \to \Lambda \pi^-)< 2.9 x 10^{-6} and B(\Xi^0 \to p \pi^-)< 8.2 x 10^{-6}, both at 90% confidence level., Comment: 4 pages, 5 figures, PRL paper

Published
2005
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83. Measurement of the Alpha Asymmetry Parameter for the Omega- to Lambda K- Decay

Author

HyperCP Collaboration, Chen, Y. C., Burnstein, R. A., Chakravorty, A., Chan, A., Choong, W. S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Gidal, G., Gu, P., Gustafson, H. R., Ho, C., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Kaplan, D. M., Lederman, L. M., Leros, N., Longo, M. J., Lopez, F., Lu, L. C., Luebke, W., Luk, K. B., Nelson, K. S., Park, H. K., Perroud, J. P., Rajaram, D., Rubin, H. A., Teng, P. K., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

We have measured the alpha parameter of the Omega- to Lambda K- decay using data collected with the HyperCP spectrometer during the 1997 fixed-target run at Fermilab. Analyzing a sample of 0.96 million Omega- to Lambda K^-, Lambda to p pi- decays, we obtain alpha_Omega*alpha_Lambda = [1.33+/-0.33(stat)+/-0.52(syst)] x 10^{-2}. With the accepted value of alpha_Lambda, alpha_Omega is found to be [2.07+/-0.51(stat)+/-0.81(syst)] x 10^{-2}., Comment: 5 pages, 4 figures, to be appeared as a Rapid Communication in Phys. Rev. D

Published
2005
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84. Evidence for the Decay Sigma+ -> p mu+ mu-

Author

Park, H. K., Burnstein, R. A., Chakravorty, A., Chen, Y. C., Choong, W. S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gustafson, H. R., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T., Kaplan, D. M., Lederman, L. M., Leros, N., Longo, M. J., Lopez, F., Lu, L. C., Luebke, W., Luk, K. B., Nelson, K. S., Perroud, J. -P., Rajaram, D., Rubin, H. A., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

We report the first evidence for the decay Sigma+ -> p mu+ mu- from data taken by the HyperCP experiment(E871) at Fermilab. Based on three observed events, the branching ratio is B(Sigma+ -> p,mu+,mu-) = [8.6 +6.6,-5.4(stat) +/-5.5(syst)] x 10**-8. The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma+ -> p P0, P0 -> mu+ mu-, with a P0 mass of 214.3 +/- 0.5 MeV/c**2 and branching ratio B(Sigma+ -> p P0; P0 -> mu+ mu-) = [3.1 +2.4,-1.(stat) +/-1.5(syst)] x 10**-8., Comment: As published in PRL

Published
2005
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85. Search for CP Violation in Charged-Xi and Lambda Hyperon Decays

Author

HyperCP Collaboration, Holmstrom, T., Leros, N., Burnstein, R. A., Chakravorty, A., Chan, A., Chen, Y. C., Choong, W. S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gu, P., Gustafson, H. R., Ho, C., Huang, M., James, C., Jenkins, C. M., Jones, T., Kaplan, D. M., Lederman, L. M., Longo, M. J., Lopez, F., Lu, L. C., Luebke, W., Luk, K. B., Nelson, K. S., Park, H. K., Perroud, J. P., Rajaram, D., Rubin, H. A., Teng, P. K., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

We have compared the proton and antiproton angular distributions in 117 million Xi-minus -> Lambda + pi-minus -> proton + pi-minus + pi-minus and 41 million anti-Xi-minus -> anti-Lamba + pi-plus -> antiproton + pi-plus + pi-plus decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter $A_{\Xi\Lambda} = \frac{\alpha_{\Xi}\alpha_{\Lambda} - \bar{\alpha}_{\Xi}\bar{\alpha}_{\Lambda}}{\alpha_{\Xi}\alpha_{\Lambda} + \bar{\alpha}_{\Xi}\bar{\alpha}_{\Lambda}} = [0.0+/-5.1(stat)+/-4.4(syst)]{\times}10^{-4}$., Comment: 4 pages, 4 figures, to be published in Phys. Rev. Lett

Published
2004
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86. High Statistics Search for the Theta+(1.54) Pentaquark State

Author

Longo, M. J., Burnstein, R. A., Chakravorty, A., Chen, Y. C., Choong, W. S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fu, Y., Gidal, G., Gustafson, H. R., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T., Kaplan, D. M., Lederman, L. M., Leros, N., Lopez, F., Lu, L. C., Luebke, W., Luk, K. B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rajaram, D., Rubin, H. A., Volk, J., White, C. G., White, S., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

We have searched for Theta+(1.54) -> K0,p decays using data from the 1999 run of the HyperCP experiment at Fermilab. We see no evidence for a narrow peak in the K0,p mass distribution near 1.54 GeV/c among 106,000 K0,p candidates, and obtain an upper limit for the fraction of Theta+(1.54) to K0,p candidates of <0.3% at 90% confidence., Comment: 4 pages, 4 figures

Published
2004
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87. HyperCP: A high-rate spectrometer for the study of charged hyperon and kaon decays

Author

HyperCP collaboration, Burnstein, R. A., Chakravorty, A., Chan, A., Chen, Y. C., Choong, W. -S., Clark, K., Dukes, E. C., Durandet, C., Felix, J., Fuzesy, R., Gidal, G., Gu, P., Gustafson, H. R., Ho, C., Holmstrom, T., Huang, M., James, C., Jenkins, C. M., Jones, T. D., Kaplan, D. M., Lederman, L. M., Leros, N., Longo, M. J., Lopez, F., Lu, L. C., Luebke, W., Luk, K. -B., Nelson, K. S., Park, H. K., Perroud, J. -P., Rajaram, D., Rubin, H. A., Teng, P. K., Turko, B., Volk, J., White, C. G., White, S. L., and Zyla, P.

Subjects
High Energy Physics - Experiment
Abstract

The HyperCP experiment (Fermilab E871) was designed to search for rare phenomena in the decays of charged strange particles, in particular CP violation in $\Xi$ and $\Lambda$ hyperon decays with a sensitivity of $10^{-4}$. Intense charged secondary beams were produced by 800 GeV/c protons and momentum-selected by a magnetic channel. Decay products were detected in a large-acceptance, high-rate magnetic spectrometer using multiwire proportional chambers, trigger hodoscopes, a hadronic calorimeter, and a muon-detection system. Nearly identical acceptances and efficiencies for hyperons and antihyperons decaying within an evacuated volume were achieved by reversing the polarities of the channel and spectrometer magnets. A high-rate data-acquisition system enabled 231 billion events to be recorded in twelve months of data-taking., Comment: 107 pages, 45 Postscript figures, 14 tables, Elsevier LaTeX, submitted to Nucl. Instrum. Meth. A

Published
2004
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88. Correlator Bank Detection of GW chirps. False-Alarm Probability, Template Density and Thresholds: Behind and Beyond the Minimal-Match Issue

Author

Croce, R. P., Demma, Th., Longo, M., Marano, S., Matta, V., Pierro, V., and Pinto, I. M.

Subjects
General Relativity and Quantum Cosmology
Abstract

The general problem of computing the false-alarm rate vs. detection-threshold relationship for a bank of correlators is addressed, in the context of maximum-likelihood detection of gravitational waves, with specific reference to chirps from coalescing binary systems. Accurate (lower-bound) approximants for the cumulative distribution of the whole-bank supremum are deduced from a class of Bonferroni-type inequalities. The asymptotic properties of the cumulative distribution are obtained, in the limit where the number of correlators goes to infinity. The validity of numerical simulations made on small-size banks is extended to banks of any size, via a gaussian-correlation inequality. The result is used to estimate the optimum template density, yielding the best tradeoff between computational cost and detection efficiency, in terms of undetected potentially observable sources at a prescribed false-alarm level, for the simplest case of Newtonian chirps., Comment: submitted to Phys. Rev. D

Published
2004
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89. How Many Templates for GW Chirp Detection? The Minimal-Match Issue Revisited

Author

Croce, R. P., Demma, Th., Longo, M., Marano, S., Matta, V., Pierro, V., and Pinto, I. M.

Subjects
General Relativity and Quantum Cosmology
Abstract

In a recent paper dealing with maximum likelihood detection of gravitational wave chirps from coalescing binaries with unknown parameters we introduced an accurate representation of the no-signal cumulative distribution of the supremum of the whole correlator bank. This result can be used to derive a refined estimate of the number of templates yielding the best tradeoff between detector's performance (in terms of lost signals among those potentially detectable) and computational burden., Comment: submitted to Class. Quantum Grav. Typing error in eq. (4.8) fixed; figure replaced in version 2

Published
2004
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90. Measurement of Decay Parameters for $\Xi^{-} \to \Lambda \pi^{-}$ Decay

Author

FNAL E756 Collaboration, Chakravorty, A., Diehl, H. T., Duryea, J., Guglielmo, G., Heller, K., Ho, P. M., James, C., Johns, K., Kaplan, D. M, Longo, M. J., Luk, K. B., Rameika, R., Rubin, H. A., Teige, S., Thomson, G. B., and Zou, Y.

Subjects
High Energy Physics - Experiment
Abstract

Based on 1.35 million polarized $\Xi^{-}$ events, we measure the parameter $\phi_{\Xi}$ to be $-1.61^{\circ} \pm 2.66^{\circ} \pm 0.37^{\circ}$ for $\Xi^{-} \to \Lambda \pi^{-}$ decay. New results for the parameters $\beta_{\Xi}$ and $\gamma_{\Xi}$ are also presented. Assuming that the CP-violating phase-shift difference is negligible, we deduce the strong phase-shift difference between the P-wave and S-wave amplitudes of the $\Lambda\pi$ final state to be $3.17^{\circ} \pm 5.28^{\circ} \pm 0.73^{\circ}$. This strong phase-shift difference reduces the theoretical uncertainty in estimating the level of CP violation in $\Xi$-hyperon decay., Comment: To be published in Physical Review Letters

Published
2003
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91. Sensitivity of the high altitude water Cherenkov detector to sources of multi-TeV gamma rays

Author

Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, de la Fuente, E, De León, C, DeYoung, T, Hernandez, R Diaz, Diaz-Velez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, Garcia-Luna, JL, Garcia-Torales, G, Garfias, F, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-García, R, Marinelli, A, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Ryan, J, Rosa-González, D, Salazar, H, Salesa, F, Sandoval, A, Santos, E, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Sparks, K, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, Zaborov, D, and Zepeda, A

Subjects
TeV gamma-ray astronomy, Water cherenkov, Cosmic ray, astro-ph.HE, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

The High Altitude Water Cherenkov (HAWC) observatory is an array of large water Cherenkov detectors sensitive to gamma rays and hadronic cosmic rays in the energy band between 100 GeV and 100 TeV. The observatory will be used to measure high-energy protons and cosmic rays via detection of the energetic secondary particles reaching the ground when one of these particles interacts in the atmosphere above the detector. HAWC is under construction at a site 4100 meters above sea level on the northern slope of the volcano Sierra Negra, which is located in central Mexico at 19 N latitude. It is scheduled for completion in 2014. In this paper we estimate the sensitivity of the HAWC instrument to point-like and extended sources of gamma rays. The source fluxes are modeled using both unbroken power laws and power laws with exponential cutoffs. HAWC, in one year, is sensitive to point sources with integral power-law spectra as low as 5×10-13 cm-2sec-1 above 2 TeV (approximately 50 mCrab) over 5 sr of the sky. This is a conservative estimate based on simple event parameters and is expected to improve as the data analysis techniques are refined. We discuss known TeV sources and the scientific contributions that HAWC can make to our understanding of particle acceleration in these sources. © 2013 Elsevier B.V. All rights reserved.

Published
2013

92. The HAWC Gamma-Ray Observatory: Sensitivity to Steady and Transient Sources of Gamma Rays

Author

Collaboration, HAWC, Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, Fuente, E de la, León, C De, DeYoung, T, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-GarcIa, R, Marinelli, A, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Salazar, H, Salesa, F, Sanchez, FE, Sandoval, A, Santos, E, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Sparks, K, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, and Zaborov, D

Subjects
astro-ph.HE
Abstract

The High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory is designed torecord air showers produced by cosmic rays and gamma rays between 100 GeV and100 TeV. Because of its large field of view and high livetime, HAWC iswell-suited to measure gamma rays from extended sources, diffuse emission, andtransient sources. We describe the sensitivity of HAWC to emission from theextended Cygnus region as well as other types of galactic diffuse emission;searches for flares from gamma-ray bursts and active galactic nuclei; and thefirst measurement of the Crab Nebula with HAWC-30.

Published
2013

93. The HAWC Gamma-Ray Observatory: Observations of Cosmic Rays

Author

Collaboration, HAWC, Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, Fuente, E de la, León, C De, DeYoung, T, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-GarcIa, R, Marinelli, A, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Salazar, H, Salesa, F, Sanchez, FE, Sandoval, A, Santos, E, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Sparks, K, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, and Zaborov, D

Subjects
astro-ph.HE
Abstract

We describe measurements of GeV and TeV cosmic rays with the High-AltitudeWater Cherenkov Gamma-Ray Observatory, or HAWC. The measurements include theobservation of the shadow of the moon; the observation of small-scale andlarge-scale angular clustering of the TeV cosmic rays; the prospects formeasurement of transient solar events with HAWC; and the observation of Forbushdecreases with the HAWC engineering array and HAWC-30.

Published
2013

94. The HAWC Gamma-Ray Observatory: Design, Calibration, and Operation

Author

Collaboration, HAWC, Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, Fuente, E de la, León, C De, DeYoung, T, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-GarcIa, R, Marinelli, A, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Salazar, H, Salesa, F, Sanchez, FE, Sandoval, A, Santos, E, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Sparks, K, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, and Zaborov, D

Subjects
astro-ph.IM, astro-ph.HE
Abstract

The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is underconstruction 4100 meters above sea level at Sierra Negra, Mexico. We describethe design and cabling of the detector, the characterization of thephotomultipliers, and the timing calibration system. We also outline anext-generation detector based on the water Cherenkov technique.

Published
2013

95. The HAWC Gamma-Ray Observatory: Dark Matter, Cosmology, and Fundamental Physics

Author

Collaboration, HAWC, Abeysekara, AU, Alfaro, R, Alvarez, C, Álvarez, JD, Arceo, R, Arteaga-Velázquez, JC, Solares, HA Ayala, Barber, AS, Baughman, BM, Bautista-Elivar, N, Belmont, E, BenZvi, SY, Berley, D, Rosales, M Bonilla, Braun, J, Caballero-Lopez, RA, Caballero-Mora, KS, Carramiñana, A, Castillo, M, Cotti, U, Cotzomi, J, Fuente, E de la, León, C De, DeYoung, T, Hernandez, R Diaz, Díaz-Vélez, JC, Dingus, BL, DuVernois, MA, Ellsworth, RW, Fernandez, A, Fiorino, DW, Fraija, N, Galindo, A, Garfias, F, González, LX, González, MM, Goodman, JA, Grabski, V, Gussert, M, Hampel-Arias, Z, Hui, CM, Hüntemeyer, P, Imran, A, Iriarte, A, Karn, P, Kieda, D, Kunde, GJ, Lara, A, Lauer, RJ, Lee, WH, Lennarz, D, Vargas, H León, Linares, EC, Linnemann, JT, Longo, M, Luna-GarcIa, R, Marinelli, A, Martinez, H, Martinez, O, Martínez-Castro, J, Matthews, JAJ, Miranda-Romagnoli, P, Moreno, E, Mostafá, M, Nava, J, Nellen, L, Newbold, M, Noriega-Papaqui, R, Oceguera-Becerra, T, Patricelli, B, Pelayo, R, Pérez-Pérez, EG, Pretz, J, Rivière, C, Rosa-González, D, Salazar, H, Salesa, F, Sanchez, FE, Sandoval, A, Santos, E, Schneider, M, Silich, S, Sinnis, G, Smith, AJ, Sparks, K, Springer, RW, Taboada, I, Toale, PA, Tollefson, K, Torres, I, Ukwatta, TN, Villaseñor, L, Weisgarber, T, Westerhoff, S, Wisher, IG, Wood, J, Yodh, GB, Younk, PW, and Zaborov, D

Subjects
astro-ph.HE
Abstract

The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is designed toperform a synoptic survey of the TeV sky. The high energy coverage of theexperiment will enable studies of fundamental physics beyond the StandardModel, and the large field of view of the detector will enable detailed studiesof cosmologically significant backgrounds and magnetic fields. We describe thesensitivity of the full HAWC array to these phenomena in five contributionsshown at the 33rd International Cosmic Ray Conference in Rio de Janeiro, Brazil(July 2013).

Published
2013

96. Estimating the proportion of health care workers susceptible to measles infection in a large university hospital in Milan, Italy, 2019−2023.

Author

Rizzo, Alberto, Mendola, M., Salari, F., Lombardi, Alessandra, Longo, M., Giacomelli, Andrea, Carrer, P., and Gismondo, Maria Rita

Subjects
MEDICAL personnel, SARS-CoV-2, AIRBORNE infection, BOOSTER vaccines, VACCINATION promotion, YOUNG women, CORONAVIRUS diseases
Abstract

The article discusses the prevalence of protective antibodies against measles among healthcare workers (HCWs) at a university hospital in Milan, Italy, from 2019 to 2023. It highlights the importance of vaccination for HCWs to prevent outbreaks of vaccine-preventable infections. The study found that 83% of HCWs had protective antibodies, with higher rates in older age groups. Seroconversion was observed in 88% of HCWs who received a booster dose of the MMR vaccine. The study emphasizes the significance of antibody testing and vaccination promotion among HCWs to prevent measles infections. [Extracted from the article]

Published
2024
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99. Search for Direct CP Violation in Non-Leptonic Decays of Charged $\Xi$ and $\Lambda$ Hyperons

Author

Luk, K. B., Diehl, H. T., Duryea, J., Guglielmo, G., Heller, K., Ho, P. M., James, C., Johns, K., Longo, M. J., Rameika, R., Teige, S., and Thomson, G. B.

Subjects
High Energy Physics - Experiment
Abstract

A search for direct CP violation in the non-leptonic decays of hyperons has been performed. In comparing the product of the decay parameters, $\alpha_{\Xi}\alpha_{\Lambda}$, in terms of an asymmetry parameter, $A_{\Xi\Lambda}$, between hyperons and anti-hyperons in the charged $\Xi \to \Lambda \pi$ and $\Lambda \to p \pi$ decay sequence, we found no evidence of direct CP violations. The parameter $A_{\Xi\Lambda}$ was measured to be $0.012 \pm 0.014$., Comment: Submitted for publication; RevTex, 13 pages, 4 figures

Published
2000
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