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PRODID:UW-Madison-Physics-Events
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SEQUENCE:0
UID:UW-Physics-Event-8918
DTSTART:20241007T200000Z
DTEND:20241007T220000Z
DTSTAMP:20260413T223322Z
LAST-MODIFIED:20240918T185005Z
LOCATION:5280 Chamberlin Hall
SUMMARY:Search for TeV Halos Using HAWC Data\, Preliminary Exam\, Hong
 yi Wu\, Physics PhD Graduate Student
DESCRIPTION:Extended gamma-ray emission at TeV energies\, known as TeV
  halos\, has been observed around a few middle-aged isolated pulsars. 
 It has been suggested that they may also be powered by millisecond pul
 sars (MSPs). Using data from the High Altitude Water Cherenkov (HAWC) 
 Observatory\, we searched for extended gamma-ray emission around 36 is
 olated middle-aged pulsars and 57 MSPs. Through a stacking analysis co
 mparing TeV flux models against a background-only hypothesis\, we iden
 tified TeV halo-like emission from isolated middle-aged pulsars at a s
 ignificance level of 5.10σ\, but found no significant emission from M
 SPs. The results imply that TeV halos may commonly exist around middle
 -aged pulsars\, while MSPs are not as efficient in producing them. The
 se findings provide a method to identify pulsars that are invisible to
  radio\, X-ray\, and GeV gamma-ray observations\, and have significant
  implications for the physics interpretation of the Galactic center Ge
 V excess and high-latitude Galactic diffuse emission. Future works inc
 luding HAWC and Fermi-LAT data analysis around TeV halo sources will a
 lso be discussed.
URL:https://www.physics.wisc.edu/events/?id=8918
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