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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

2437 results found.

  1. GRB 260109A: Fermi GBM Final Real-time Localization
  2. Fermi GRB 260107A: Global MASTER-Net observations report
  3. GRB 260102A: AbAO optical observations
  4. GRB 260107A: Fermi GBM Final Real-time Localization
  5. EP260105b/EP-WXT trigger 01709251028: Einstein Probe detection of an X-ray transient
  6. The EP-WXT trigger 01709251112 is likely a flaring star
  7. Fermi GRB 260105A: Global MASTER-Net observations report
  8. GRB 260105B: Fermi GBM Detection
  9. EP260105a: FTW optical observations
  10. EP260104a: FTW optical observations
  11. GRB 260105B: BALROG localization (Fermi Trigger 789348101 / GRB 260105973)
  12. GRB 260105A: SVOM/GRM observation
  13. GRB 260105B: SVOM/GRM observation
  14. The EP-WXT trigger 01709251028 is likely a flaring star
  15. FRB 20251229A: COLIBRÍ optical upper limits
  16. Fermi GRB 260105B: Global MASTER-Net observations report
  17. EP260105a: SVOM/VT optical upperlimit
  18. GRB 260105B: Fermi GBM Final Real-time Localization
  19. GRB 260105A: Fermi GBM Final Real-time Localization
  20. FRB 20251229A: A potentially hyperactive repeating fast radio burst source
  21. EP260105a: refined analysis of the EP-WXT and EP-FXT observations
  22. EP260105a: LCO Optical Upper limit
  23. EP260104a: Global MASTER-Net observations report
  24. EP260104a: Einstein Probe detection of a fast X-ray transient
  25. GRB 260101A: COLIBRÍ optical upper limits
  26. EP260105a: Global MASTER-Net observations report
  27. EP260105a: Einstein Probe detection of an X-ray transient
  28. GRB 260103A: Insight-HXMT/HE detection
  29. GRB 260104A: COLIBRÍ optical upper limits
  30. GRB 260104C: Fermi GBM Final Real-time Localization
  31. Fermi GRB 260104B: Global MASTER-Net observations report
  32. Swift GRB 260104A: Global MASTER-Net observations report
  33. GRB 260103A: GECAM-B observation of a burst
  34. GRB 260104B: Fermi GBM Final Localization
  35. GRB 260103A: SVOM/GRM observation of a possible GRB
  36. GRB 260101A: COLIBRÍ optical observations
  37. SVOM GRB260103.08: Global MASTER-Net observations report
  38. GRB 260102B: Fermi GBM Final Real-time Localization
  39. SVOM GRB260102A: Global MASTER-Net observations report
  40. Fermi GBM Sub-Threshold Detection of GRB 260102A
  41. GRB 260102A: EP-FXT follow-up observation
  42. EP260101a: Global MASTER-Net observations report
  43. GRB 260102A: LCO optical upper limits
  44. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  45. Fermi Gamma-ray Burst Monitor trigger 789047602/260102495 is not a GRB
  46. GRB 260102A: SVOM/VT optical counterpart
  47. GRB 260101A: Fermi GBM Observation
  48. EP260101a: refined analysis of the EP-WXT and EP-FXT observations
  49. GRB 260102A: SVOM detection of a burst
  50. GRB 260101A: GECAM-B detection
  51. GRB 260101A: NOT spectroscopic observations
  52. GRB 260101A: SVOM/GRM observation
  53. Swift GRB 260101A: Global MASTER-Net observations report
  54. EP260101a: Einstein Probe detection of an X-ray transient
  55. GRB 260101A: OSIRIS+ redshift z = 2.623 for the new year burst
  56. GRB 260101A: LCO detection of the optical counterpart
  57. GRB 260101A: Fermi GBM Final Real-time Localization
  58. Konus-Wind detection of GRB 251103A
  59. GRB 251013B: SVOM/GRM observation
  60. GRB 250625A: Swift/UVOT Upper Limits
  61. GRB 250603A: Swift/UVOT Upper Limits
  62. GRB 250421A: AstroSat CZTI detection
  63. GRB 250302A: Fermi GBM Observation
  64. GRB 241228A: Swift/UVOT Upper Limits
  65. Integral GRB241215.58: Global MASTER-Net observations report
  66. GRB 240802A: AstroSat CZTI detection of a long burst
  67. GRB 240712A: Swift/UVOT Upper Limits
  68. GRB 240713B: AstroSat CZTI detection of a long burst
  69. Fermi GRB 240422A: Global MASTER-Net observations report
  70. GRB 240225B: Glowbug gamma-ray detection
  71. Fermi trigger No 726774492: Global MASTER-Net observations report
  72. GRB 240102C: AstroSat CZTI detection
  73. GRB 230815A: ATCA detection of radio counterpart
  74. GRB 230524A: AstroSat CZTI detection
  75. GRB 230321B: AstroSat CZTI detection
  76. GRB 230307A: Detection by GRBAlpha
  77. GRB 221009A: Detection by GRBAlpha
  78. GRB 220730A: Swift/UVOT Upper Limits
  79. Konus-Wind detection of GRB 220627A
  80. GRB 220518A: Swift/UVOT Detection
  81. Swift GRB210731.93: Global MASTER-Net observations report
  82. Fermi trigger No 647805873: Global MASTER-Net observations report
  83. GRB 210323A: Swift/UVOT Upper Limits
  84. GRB 210318B: Swift/UVOT Upper Limits
  85. GRB 201001A: Swift/UVOT Upper Limits
  86. GRB 200906A: Swift/UVOT Upper Limits
  87. Fermi GRB 200702A: Global MASTER-Net observations report
  88. Fermi trigger No 606263732: Global MASTER-Net observations report
  89. Swift GRB200306.95: Global MASTER-Net observations report
  90. LIGO/Virgo S191216ap: MASTER optical observation
  91. LIGO/Virgo S191216ap: Upper limits from Fermi-GBM Observations
  92. LIGO/Virgo S191216ap: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  94. Fermi trigger No 581645543 Global MASTER-Net observations report
  95. GRB 181203A: Swift/UVOT Upper Limits
  96. LIGO/Virgo G298048: Effelsberg 100-m Radio Telescope observations of SSS17a
  97. LIGO/Virgo G275697: Further Swift-XRT sources
  98. GRB 170208A: Swift/UVOT Upper Limits
  99. GRB 161219B: Swift/UVOT Detection
  100. GRB 160521B: Swift/UVOT Upper Limits

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