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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').
Advanced Search

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"

2429 results found.

  1. EP260105a: FTW optical observations
  2. EP260104a: FTW optical observations
  3. GRB 260105B: BALROG localization (Fermi Trigger 789348101 / GRB 260105973)
  4. GRB 260105A: SVOM/GRM observation
  5. GRB 260105B: SVOM/GRM observation
  6. The EP-WXT trigger 01709251028 is likely a flaring star
  7. FRB 20251229A: COLIBRÍ optical upper limits
  8. Fermi GRB 260105B: Global MASTER-Net observations report
  9. EP260105a: SVOM/VT optical upperlimit
  10. GRB 260105B: Fermi GBM Final Real-time Localization
  11. GRB 260105A: Fermi GBM Final Real-time Localization
  12. FRB 20251229A: A potentially hyperactive repeating fast radio burst source
  13. EP260105a: refined analysis of the EP-WXT and EP-FXT observations
  14. EP260105a: LCO Optical Upper limit
  15. EP260104a: Global MASTER-Net observations report
  16. EP260104a: Einstein Probe detection of a fast X-ray transient
  17. GRB 260101A: COLIBRÍ optical upper limits
  18. EP260105a: Global MASTER-Net observations report
  19. EP260105a: Einstein Probe detection of an X-ray transient
  20. GRB 260103A: Insight-HXMT/HE detection
  21. GRB 260104A: COLIBRÍ optical upper limits
  22. GRB 260104C: Fermi GBM Final Real-time Localization
  23. Fermi GRB 260104B: Global MASTER-Net observations report
  24. Swift GRB 260104A: Global MASTER-Net observations report
  25. GRB 260103A: GECAM-B observation of a burst
  26. GRB 260104B: Fermi GBM Final Localization
  27. GRB 260103A: SVOM/GRM observation of a possible GRB
  28. GRB 260101A: COLIBRÍ optical observations
  29. SVOM GRB260103.08: Global MASTER-Net observations report
  30. GRB 260102B: Fermi GBM Final Real-time Localization
  31. SVOM GRB260102A: Global MASTER-Net observations report
  32. Fermi GBM Sub-Threshold Detection of GRB 260102A
  33. GRB 260102A: EP-FXT follow-up observation
  34. EP260101a: Global MASTER-Net observations report
  35. GRB 260102A: LCO optical upper limits
  36. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  37. Fermi Gamma-ray Burst Monitor trigger 789047602/260102495 is not a GRB
  38. GRB 260102A: SVOM/VT optical counterpart
  39. GRB 260101A: Fermi GBM Observation
  40. EP260101a: refined analysis of the EP-WXT and EP-FXT observations
  41. GRB 260102A: SVOM detection of a burst
  42. GRB 260101A: GECAM-B detection
  43. GRB 260101A: NOT spectroscopic observations
  44. GRB 260101A: SVOM/GRM observation
  45. Swift GRB 260101A: Global MASTER-Net observations report
  46. EP260101a: Einstein Probe detection of an X-ray transient
  47. GRB 260101A: OSIRIS+ redshift z = 2.623 for the new year burst
  48. GRB 260101A: LCO detection of the optical counterpart
  49. GRB 260101A: Fermi GBM Final Real-time Localization
  50. Konus-Wind detection of GRB 251103A
  51. GRB 251013B: SVOM/GRM observation
  52. GRB 250625A: Swift/UVOT Upper Limits
  53. GRB 250603A: Swift/UVOT Upper Limits
  54. GRB 250421A: AstroSat CZTI detection
  55. GRB 250302A: Fermi GBM Observation
  56. GRB 241228A: Swift/UVOT Upper Limits
  57. Integral GRB241215.58: Global MASTER-Net observations report
  58. GRB 240802A: AstroSat CZTI detection of a long burst
  59. GRB 240712A: Swift/UVOT Upper Limits
  60. GRB 240713B: AstroSat CZTI detection of a long burst
  61. Fermi GRB 240422A: Global MASTER-Net observations report
  62. GRB 240225B: Glowbug gamma-ray detection
  63. Fermi trigger No 726774492: Global MASTER-Net observations report
  64. GRB 240102C: AstroSat CZTI detection
  65. GRB 230815A: ATCA detection of radio counterpart
  66. GRB 230524A: AstroSat CZTI detection
  67. GRB 230321B: AstroSat CZTI detection
  68. GRB 230307A: Detection by GRBAlpha
  69. GRB 221009A: Detection by GRBAlpha
  70. GRB 220730A: Swift/UVOT Upper Limits
  71. Konus-Wind detection of GRB 220627A
  72. GRB 220518A: Swift/UVOT Detection
  73. Swift GRB210731.93: Global MASTER-Net observations report
  74. Fermi trigger No 647805873: Global MASTER-Net observations report
  75. GRB 210323A: Swift/UVOT Upper Limits
  76. GRB 210318B: Swift/UVOT Upper Limits
  77. GRB 201001A: Swift/UVOT Upper Limits
  78. GRB 200906A: Swift/UVOT Upper Limits
  79. Fermi GRB 200702A: Global MASTER-Net observations report
  80. Fermi trigger No 606263732: Global MASTER-Net observations report
  81. Swift GRB200306.95: Global MASTER-Net observations report
  82. LIGO/Virgo S191216ap: MASTER optical observation
  83. LIGO/Virgo S191216ap: Upper limits from Fermi-GBM Observations
  84. LIGO/Virgo S191216ap: Identification of a GW compact binary merger candidate
  85. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  86. Fermi trigger No 581645543 Global MASTER-Net observations report
  87. GRB 181203A: Swift/UVOT Upper Limits
  88. LIGO/Virgo G298048: Effelsberg 100-m Radio Telescope observations of SSS17a
  89. LIGO/Virgo G275697: Further Swift-XRT sources
  90. GRB 170208A: Swift/UVOT Upper Limits
  91. GRB 161219B: Swift/UVOT Detection
  92. GRB 160521B: Swift/UVOT Upper Limits
  93. GRB 160412A: Swift/UVOT Upper Limits
  94. GRB 150720A: Swift/UVOT Upper Limits
  95. GRB 150626A: Swift/UVOT Upper Limits
  96. GRB 150615A: Swift/UVOT Detection
  97. GRB 150301B: X-shooter spectroscopy
  98. GRB 150101A: Swift/UVOT Upper Limits
  99. GRB 140829A: Fermi GBM Detection
  100. GRB 140219A: MASTER before and after GRB observational arguments of the exceptionally Dark GRB

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