Bulletin of the American Physical Society
APS April Meeting 2017
Volume 62, Number 1
Saturday–Tuesday, January 28–31, 2017; Washington, DC
Session B4: Neutrino Astronomy and Search for Counterparts |
Hide Abstracts |
Sponsoring Units: DAP Chair: Naoko Kurahashi Neilson, Drexel University Room: Virginia A |
Saturday, January 28, 2017 10:45AM - 10:57AM |
B4.00001: Search for Neutrinos from the Supergalactic Plane Stephen Sclafani Point sources that produce high energy neutrinos remain elusive. While multiple studies have focused on high energy cosmological phenomenon such as gamma ray bursts, few have looked for correlation with local superstructures like the supergalactic plane that can produce these neutrinos not only directly but also through secondary cosmic ray interactions. Interaction within galactic media can produce neutrinos that can be observed in IceCube, a Cherenkov detector buried at the south pole in one and a half kilometers of glacial ice. The density of local galaxies in the sky, as surveyed by the Two Micron All Sky Survey (2MASS) provide a spacial template for the supergalactic plane. The 2MASS Survey is an infrared survey of over 300 million astrophysical objects and contains over 45,000 local galaxies' position and redshift. Spacial templates for the supergalactic plane are tested with one year of event data from Icecube. This analysis will aid in the understanding of the methods of production of high energy neutrinos and cosmic rays. [Preview Abstract] |
Saturday, January 28, 2017 10:57AM - 11:09AM |
B4.00002: Search for Blazar Flux-Correlated TeV Neutrinos in IceCube 40-String Data Colin Turley, Derek Fox, Kohta Murase We present a targeted search for blazar TeV flux-correlated high-energy neutrinos from six bright northern blazars in the IceCube “40-string" sample of TeV neutrinos from 2008-2009. We use VERITAS lightcurves to identify periods of excess and flaring emission and search for an excess of neutrinos during these intervals relative to the atmospheric neutrino background. We make two searches: One for excess neutrinos from Mrk 421, and one for neutrinos associated with the brightest emission periods of five other blazars. We find no significant excess of neutrinos from the blazar directions during the predefined temporal windows, and derive upper limits on the number of blazar-associated neutrinos from each search. These upper limits are sufficiently close to the physically-interesting regime that we anticipate future analyses using already-collected data will either constrain models or yield discovery of the first blazar-associated high-energy neutrinos. [Preview Abstract] |
Saturday, January 28, 2017 11:09AM - 11:21AM |
B4.00003: Search for high energy neutrinos from Seyfert galaxies using IceCube Ben Relethford Since its construction began in 2005, The IceCube Neutrino Observatory, a cubic kilometer Cherenkov detector buried deep in the geographic South Pole ice, has searched for a high-energy astrophysical neutrino flux. In 2013, IceCube observed such a flux deviating at least 5.7$\sigma$ above atmospheric backgrounds. However, analyses of promising source candidates such as blazars (a type of radio-loud Active Galactic Nucleus, or AGN) and gamma ray bursts have found no evidence of neutrino emission, placing stringent constraints on their possible contribution to the observed extraterrestrial neutrino flux. This analysis considers a numerous yet comparatively low-intensity type of radio-quiet AGN known as Seyfert galaxies as a new candidate source of high energy astrophysical neutrinos. We obtain a catalog of Seyfert galaxies from the 70 month catalog of high-energy x-ray sources as identified by the BAT detector on the \textit{Swift} satellite. We simultaneously study these Seyfert galaxies via a stacking analysis, which is particularly well-suited to a source class with high abundance but relatively low-intensity. This analysis will probe for the first time whether Seyfert galaxies contribute significantly to the observed, but so far unresolved astrophysical neutrino flux. [Preview Abstract] |
Saturday, January 28, 2017 11:21AM - 11:33AM |
B4.00004: Constraining a Galactic Origin of the IceCube Neutrinos with HAWC All-Sky Gamma-Ray Observations John Pretz The origin of the TeV-PeV high-energy astrophysical neutrino events seen in IceCube data is hotly debated. If the events are not due to dark matter, the relative isotropy of the signal points to a dominant extra-Galactic population. Nevertheless sub-dominant Galactic scenarios have not been ruled out. We expect the production of Galactic TeV-PeV neutrinos (via charged pion decay) to be accompanied by high-energy gamma rays (from neutral pion decay). Data from the High Altitude Water Cherenkov Observatory (HAWC) reveal a strong detection of emission from the plane of the galaxy, providing a constraint on the fraction of the IceCube flux that can be of Galactic origin. A search for large-scale isotropic photon emission has the potential to provide analogous constraints. I will present HAWC's measurement of the total TeV emission in the Northern half of the Galactic plane along with current limits on isotropic diffuse gamma-ray emission and discuss the implications for the origin of the IceCube neutrinos. [Preview Abstract] |
Saturday, January 28, 2017 11:33AM - 11:45AM |
B4.00005: Constraining the extragalactic origin of IceCube’s neutrinos using HAWC Ignacio Taboada IceCube has observed an astrophysical isotropic flux of neutrinos in the 10 TeV - 8 PeV range. Though an extragalactic origin is usually assumed, no unequivocal association with astrophysical objects has been made. It is often assumed that the neutrino sources are also cosmic ray sources and therefore gamma-ray sources. HAWC has studied 2/3 of the sky with 500 GeV - 100 TeV photons. Only two, previously known, objects are found in the extragalactic sky by HAWC: Mrk 421 and Mrk 501. The lack of observed extragalactic gamma-ray sources by HAWC can be used to set a lower bound on the local Universe density of optically thin neutrino sources. This in turn can be used to disqualify classes of potential sources. [Preview Abstract] |
Saturday, January 28, 2017 11:45AM - 11:57AM |
B4.00006: The Search for Sources of High Energy Astrophysical Neutrinos with VERITAS Ava Ghadimi, Marcos Santander The IceCube collaboration has reported the detection of an all-sky astrophysical flux of high-energy neutrinos. So far, no neutrino point sources have been detected. The VERITAS (Very Energetic Radiation Imaging Telescope Array System) gamma-ray observatory has observed the sky in the direction of muon neutrino events of poten- tial astrophysical origin looking for gamma-ray emission. Hadronic gamma-rays are expected to be produced in the same cosmic-ray interactions that lead to the emission of the high-energy neutrinos detected by IceCube. We present results from follow-up VERITAS observations of 28 muon neutrino events detected by IceCube with energies above 100 TeV. No gamma-ray excess was detected at the locations of the neutrino events so gamma-ray flux upper limits were calculated. We will discuss how these results correlate to the all-sky neutrino flux. [Preview Abstract] |
Saturday, January 28, 2017 11:57AM - 12:09PM |
B4.00007: Searching for astrophysical neutrinos with Super-Kamiokande Erin O'Sullivan After accumulating data for 20 years, Super-Kamiokande is a trove of information. Traditionally known for the measurement of atmospheric and solar neutrinos as well as the search for nucleon decay, Super-Kamiokande has also been used to search for neutrinos with astrophysical origins, including relic supernovae, GRBs, and supernova remnants. This talk will focus on the recent effort to measure astrophysical neutrinos in Super-Kamiokande from sources such as dark matter annihilation and from the gravitational wave events reported by LIGO. [Preview Abstract] |
Saturday, January 28, 2017 12:09PM - 12:21PM |
B4.00008: Prospects for Detecting Galactic Sources of Cosmic Neutrinos with IceCube Ali Kheirandish, Francis Halzen, Vivana Niro We evaluate the prospects for detecting the neutrino emission from sources in the Galactic plane assuming that the highest energy photons originate from the decay of pions, which yields a straightforward prediction for the neutrino flux from the decay of the associated production of charged pions. Four promising sources are identified based on having a large flux and a flat spectrum. We subsequently evaluate the probability of their identification in IceCube data as a function of time. We show that observing them over the twenty-year lifetime of the instrumentation is likely, and that some should be observable at the $3\,\sigma$ level with six years of data. In the absence of positive results, we derive constraints on the spectral index and cut-off energy of the sources, assuming a hadronic acceleration mechanism. [Preview Abstract] |
Saturday, January 28, 2017 12:21PM - 12:33PM |
B4.00009: A New Method for Finding Point Sources in High-Energy Neutrino Data Mark Giovinazzi The IceCube Neutrino Observatory has not yet been able to identify an astrophysical point source from which a high-energy neutrino has originated. In this analysis, we implement a new method for finding such point sources by choosing to examine pairs of detected events rather than individual ones, noting that clusters of events are more likely to come from a single source than those from widely different parts of the sky. We wish to measure the angular distances between all possible pairs of events, scaling each by the pair's angular resolution errors summed in quadrature. Furthermore, we compare this result to statistically generated distributions of both a diffuse and a clustered set of events. Our new method is thus designed to teach us exactly how point-source-like our sample of detected events really is. We propose that our analysis should be able to determine the origins of any given clustering of events within the IceCube data, allowing us to discover the first neutrino point source in history. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700