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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"

28059 results found.

  1. GRB 210202A: Fermi GBM detection
  2. GRB 210202A: Fermi-LAT detection
  3. GRB 210202A: BALROG localization (Fermi Trigger / GRB 210202841)
  4. GRB 210131A: GECAM detection
  5. GRB 210129A: Insight-HXMT/HE detection
  6. Continued Chandra observations of GW170817 at ~3.3 years since merger
  7. Konus-Wind detection of two bright bursts from SGR 1935+2154
  8. GRB 140330A: Swift-XRT refined Analysis
  9. GRB 140320B: Swift-XRT refined Analysis
  10. GRB 210126A: AstroSat CZTI detection
  11. GRB 210123A: AstroSat CZTI detection
  12. IPN triangulation of a bright burst from SGR 1935+2154
  13. GECAM detection of a short burst probably from SGR 1935+2154
  14. GRB 210120A: Fermi GBM detection
  15. HAWC Transient event on 2021/01/25
  16. GRB 210126A: GECAM detection
  17. GRB 210126A: BALROG localization (Fermi Trigger / GRB 210126417)
  18. GRB 210124B: Insight-HXMT/HE detection
  19. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  20. GRB 210123A: Insight-HXMT/HE detection
  21. GRB 210121A: GECAM detection
  22. GRB 210121A: Insight-HXMT/HE detection
  23. GRB 210120A : 1.3m DFOT optical observations
  24. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  25. GRB 210116: AstroSat LAXPC detection
  26. GRB 210104A: 3.6m DOT optical upper limit
  27. GRB 210120A: BALROG localization (Fermi Trigger 632819449 / GRB 210120299)
  28. GRB 210112A: 3.6m DOT optical detection
  29. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  30. ZTF21aaeyldq: GROND observations
  31. GRB 210119A: Insight-HXMT/HE detection
  32. ZTF21aaeyldq: LBT near-infrared observations
  33. GRB 210112A: Insight-HXMT/HE detection
  34. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  35. ZTF21aaeyldq: KPED observations
  36. Correction to GCN 29288: NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS observation
  37. GRB 201221D: near-infrared observation with LBT
  38. ZTF21aaeyldq: NOT optical observations
  39. ZTF21aaeyldq: Lowell Discovery Telescope observations
  40. ZTF21aaeyldq: observations with the 3.6m Devasthal Optical Telescope
  41. GRB 201015A: evidence of supernova in LBT spectra
  42. GRB 210112A: Swift/UVOT Detection
  43. GRB 210112A: Mondy optical observations
  44. GRB 210104A: AstroSat CZTI detection
  45. NuEm-210111A: MAXI/GSC upper limit
  46. GRB 210112A: Swift-BAT refined analysis
  47. GRB 210112A: OSN Reddened Afterglow Detection
  48. GRB 210112A: Swift-XRT refined Analysis
  49. NuEm-210111A : No neutrino counterpart in ANTARES
  50. GRB 210112A: Kitab a optical upper limit
  51. GRB 210104A: AROMA-N Optical Afterglow Detection
  52. GRB 210112A: Enhanced Swift-XRT position
  53. GRB 210112A: Swift detection of a burst with an optical counterpart
  54. NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  55. MAXI GRB210110.64: Global MASTER-Net observations report
  56. GRB 210110A: MAXI/GSC detection
  57. GRB 210109A: MAXI/GSC detection
  58. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  59. Correction to GCN 29278: GRB 201216C XRT refined analysis
  60. GRB 210108A: BALROG localization (Fermi Trigger 631793415 / GRB 210108424)
  61. GRB 201216C: Swift-XRT refined Analysis
  62. GRB 210104A: SAO RAS optical observations
  63. GRB 201227A: ASIM observation
  64. GRB 210104A: GMG observations
  65. GRB210104A: VIRT optical transient detection.
  66. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  67. GRB 210102B: further Swift-XRT observations
  68. GRB 210102B: Assy optical afterglow identification
  69. GRB 210104A: iTelescope optical upper limit
  70. GRB 210104B: Swift-BAT refined analysis
  71. GW170817: HST observations at 3.4 years from merger
  72. GRB 210104A: early ATLAS detections of the bright afterglow
  73. GRB 210104A: Swift-XRT refined Analysis
  74. GRB 210104B: Swift/UVOT Upper Limits
  75. GRB 210104B: Swift-XRT refined Analysis
  76. GRB 210104B: Assy optical upper limit
  77. GRB 210104A: DOAO optical afterglow observations
  78. GRB 210104B: Enhanced Swift-XRT position
  79. GRB 210104A: Nanshan/NEXT optical powerlaw decay
  80. GRB 210104A: Swift-BAT refined analysis
  81. GRB 210104B: Nanshan/NEXT optical upper limit
  82. GRB 210104A: Swift/UVOT Detection
  83. GRB 210104A: Fermi GBM detection
  84. GRB 210104A: Enhanced Swift-XRT position
  85. GRB 210104B: Swift detection of a burst
  86. GRB 210104A: MITSuME Ishigaki optical observation
  87. GRB 210104A: MITSuME Akeno optical observation
  88. GRB 210104A: BALROG localization (Fermi Trigger 631452424 / GRB 210104477)
  89. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  90. GRB 210102C: Swift-BAT refined analysis
  91. GRB 210102B: Swift-XRT observations
  92. GRB 210102C: Fermi GBM detection
  93. MAXI GRB210102.38: Global MASTER-Net observations report
  94. GRB 210102B: MAXI/GSC detection
  95. INTEGRAL Weak #8913: AROMA-N Optical Observation
  96. Swift Trigger 1015615 is not a GRB
  97. Fermi trigger No 631119348: Global MASTER-Net observations report
  98. GRB 210101A: BALROG localization (Fermi Trigger 631205591 / GRB 210101620)
  99. GRB 210101A: Fermi GBM Final Real-time Localization
  100. GRB 201229A: Swift/UVOT Detection

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