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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

20955 results found.

  1. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  2. Trigger 657564 / GRB 151004A: Swift/UVOT Upper Limits
  3. Swift Trigger 657564: MASTER-NET early optical observations.
  4. LIGO/Virgo G184098: MASTER OTs detection and Scenario Machine prediction
  5. GRB 151001A: RATIR Observations
  6. GRB 151001B: Swift/UVOT Upper Limits
  7. GRB 151001A: Swift/UVOT Detection
  8. GRB 151001B: MASTER-NET early optical observations.
  9. GRB 150925A: Swift/UVOT Upper Limits
  10. LIGO/Virgo G184098: LOFAR follow-up
  11. LIGO/Virgo G184098: ASKAP followup
  12. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  13. LIGO/Virgo G184098: optical transient search with Kiso Schmidt telescope and KWFC on behalf of J-GEM collaboration
  14. LIGO/VIRGO G184098 : classifications of transients from the LSQ observations
  15. LIGO/Virgo G184098: transient search with VISTA
  16. ANTARES neutrino detection: Fermi GBM Observations
  17. LIGO/Virgo G184098: DESGW followup program
  18. LIGO/Virgo G184098: SkyMapper observations
  19. LIGO/Virgo G184098: TAROT network optical observations
  20. LIGO/Virgo G184098: La Silla - QUEST Followup
  21. LIGO/Virgo G184098: Swift follow-up observations
  22. LIGO/Virgo G184098: MWA Followup
  23. LIGO/Virgo G184098: DESGW followup program
  24. LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
  25. LIGO/Virgo G184098: Observations from the TOROS collaboration
  26. LIGO/Virgo G184098: iPTF Optical Transient Candidates
  27. LIGO/Virgo G184098: VST-ESO PARANAL observations
  28. LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
  29. Instructions for reporting follow-up observations related to LIGO/Virgo G184098
  30. LIGO/Virgo G184098: observations by MASTER
  31. LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
  32. LIGO/Virgo G184098: Swift follow-up observations
  33. GRB 150910A: AAO optical observations
  34. GRB150915A : IRSF NIR upper limits
  35. GRB 150915A: NOT observations of a brightening afterglow
  36. GRB 150915A: Swift UVOT upper limits
  37. GRB 150910A: Mt. Terskol observatory optical observations
  38. GRB 150910A: TSHAO optical observations
  39. GRB 150915A: GROND detection of an optical counterpart candidate
  40. GRB 150915A: MASTER-NET optical observations
  41. GRB 150910A: T100 observations
  42. GRB 150911A: GROND Upper Limits
  43. GRB 150910A: Continued RATIR Observations
  44. GRB 150907A: Swift-XRT afterglow detection
  45. GRB 150912A: Swift-XRT and UVOT observations
  46. GRB 150910A: RATIR Observations
  47. GRB 150912A: MASTER-IAC optical observations
  48. GRB 150912A: Swift ToO observations
  49. GRB150910A: P60 Observations
  50. GRB150911A: P60 Observations
  51. GRB 150911A: Swift/UVOT Upper Limits
  52. GRB 150910A: AAO optical observations
  53. GRB 150910A: Chuguev observatory optical observations
  54. GRB 150910A: VLA Detection
  55. GRB 150910A: continued SAO RAS optical observations
  56. GRB150911A MITSuME Okayama Ks-band upper-limit
  57. GRB 150910A: TSHAO optical observations
  58. GRB 150910A: NOT observations of the afterglow
  59. GRB 150910A: MITSuME Okayama Ks-band Observation
  60. GRB 150910A: GROND observation of the afterglow
  61. GRB 150910A: SAO RAS optical photometry
  62. GRB 150910A: Swift/UVOT Detection of a Brightening Afterglow
  63. GRB 150910A: Nanshan optical observations
  64. GRB 150910A: LCOGT FTN afterglow observations
  65. GRB 150910A: KAIT Optical Afterglow Detection
  66. Short GRB 150906B: proximity to NGC 3313 galaxy group
  67. GRB150907A: Swift/UVOT observations
  68. GRB 150907B: MASTER-SAAO early optical observations
  69. GRB 150907B: GROND Upper Limits
  70. GRB 150907B: Swift-XRT observations
  71. GRB 150907A: Swift-XRT observations
  72. GRB 150907A: Tiled Swift observations
  73. GRB 150818A: TSHAO and SAO RAS optical observations
  74. GRB 150902A: Swift-XRT afterglow detection
  75. ANTARES neutrino detection: ANU 2.3m and Kepler K2 Observations of the Swift x-ray source
  76. ANTARES neutrino detection: CAHA photometry & spectroscopy of the Swift source
  77. ANTARES neutrino Alert150901.32 alert and Swift XRT counterpart: MASTER optical observations and new possible candidate
  78. ANTARES neutrino detection and Swift/XRT counterpart: GMG observation
  79. GRB 150902A: Swift/UVOT Upper Limits
  80. GRB 150902A: Swift-XRT observations
  81. GRB 150831A: 9.8 GHz VLA upper limits
  82. GRB 150902A: MASTER-SAAO optical observations
  83. ANTARES neutrino detection and possible Swift X-ray counterpart
  84. GRB 150902A: Swift ToO observations
  85. GRB 150831B: Swift/UVOT Upper Limits
  86. GRB 150821A: Flattening in the UVOT light curve
  87. GRB 150831B: MASTER-IAC early optical observations
  88. GRB 150831A: GROND Upper Limits
  89. GRB 150831A: Swift/UVOT Upper Limits
  90. GRB 150831B: Swift-XRT observations
  91. GRB 150831B: Swift detection of a probable burst
  92. GRB 150818A: possible SN rise in light curve of Mondy observations
  93. GRB 150821A: LCOGT Siding Springs early observations
  94. GRB 150821A: LCOGT Sutherland observations
  95. GRB 150821A: GROND afterglow observations
  96. GRB 150821A: Swift/UVOT Detection
  97. GRB 150818A: continued Mondy optical observations
  98. GRB 150821A: VLT/X-shooter redshift
  99. Swift Trigger 652824: Is most likely a noise fluctuation in the direction of M31
  100. GRB 120729A: KAIT Optical Observations

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