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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"
  1. LIGO/Virgo/KAGRA S240514x: Updated Sky localization
  2. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  3. GRB 240514B: Fermi GBM Detection
  4. LIGO/Virgo/KAGRA S240422ed: Las Cumbres Observatory Follow-up Observations of the Localization Region
  5. GRB 240513A: Fermi GBM observation
  6. GRB 240513A: Swift-XRT observations
  7. LIGO/Virgo/KAGRA S240513ei: Updated Sky localization
  8. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  9. GRB 240514D: AstroSat CZTI detection
  10. GRB 240514C: Fermi GBM Final Real-time Localization
  11. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  12. Fermi GRB 240514B: Global MASTER-Net observations report
  13. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  14. Fermi Gamma-ray Burst Monitor triggers 737345659/240514093 and GRB240514A are not GRBs
  15. GRB 240514B: Fermi GBM Final Real-time Localization
  16. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  18. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  19. GRB 240514A: Fermi GBM Final Real-time Localization
  20. GRB 240513A: Tiled Swift observations
  21. LAT GRB240513.31: Global MASTER-Net observations report
  22. GRB 240513A: Fermi-LAT detection
  23. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  24. GRB 240511A: Fermi GBM Observation
  25. GRB 240511A: Swift-BAT refined analysis
  26. Fermi GRB 240513B: Global MASTER-Net observations report
  27. Fermi trigger No 737277727: Global MASTER-Net observations report
  28. GRB 240513B: Fermi GBM Final Real-time Localization
  29. GRB 240513A: AstroSat CZTI detection
  30. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  31. Fermi trigger No 737258655: Global MASTER-Net observations report
  32. GRB 240511A: J-band observations with WINTER
  33. Fermi trigger No 737247400: Global MASTER-Net observations report
  34. Fermi trigger No 737244199: Global MASTER-Net observations report
  35. Fermi trigger No 737218721: Global MASTER-Net observations report
  36. Fermi trigger No 737196587: Global MASTER-Net observations report
  37. Fermi trigger No 737168073: Global MASTER-Net observations report
  38. GRB 240511A: Enhanced Swift-XRT position
  39. GRB 240511A : MITSuME Akeno optical upper limits
  40. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  41. GRB 240511A: Swift-XRT refined Analysis
  42. GRB 240511A: optical afterglow detection from the NOT
  43. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  44. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  45. Fermi GBM trigger 737105243/240511311 is not a GRB
  46. Fermi trigger No 737173236: Global MASTER-Net observations report
  47. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  48. Fermi GRB 240511A: Global MASTER-Net observations report
  49. Swift GRB 240511A: Global MASTER-Net observations report
  50. Fermi trigger No 737105243: Global MASTER-Net observations report
  51. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  52. Fermi trigger No 737152719: Global MASTER-Net observations report
  53. GRB 240511A: Prompt enhanced Swift-XRT position
  54. GRB 240511A: Swift detection of a burst
  55. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  56. GRB 240511A: Fermi GBM Final Real-time Localization
  57. Fermi trigger No 737102480: Global MASTER-Net observations report
  58. Fermi trigger No 737111207: Global MASTER-Net observations report
  59. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  60. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  61. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  62. LIGO/Virgo/KAGRA S240422ed: P200 observations of AT2024hit
  63. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  64. Fermi trigger No 736967879: Global MASTER-Net observations report
  65. EP240506a: Xinglong optical upper limit
  66. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  67. EP240506a: CrAO ZTSH optical upper limit
  68. GRB 240504A: Fermi GBM Observation
  69. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  70. EP240506a: Archival radio searching
  71. EP240506a: TRT optical upper limit
  72. EP240506a: BOOTES Network optical upper limit
  73. LIGO/Virgo/KAGRA S240507p: Updated Sky localization and EM Bright Classification
  74. LIGO/Virgo/KAGRA S240422ed: Upper limits from a two-week IceCube neutrino search
  75. Fermi trigger No 736733320: Global MASTER-Net observations report
  76. EP240506a: Optical upper limit with Kinder observations
  77. IPN triangulation of GRB 240504A
  78. GRB 240502A: 1.3m DFOT Optical upper limit
  79. EP240506a: EP-WXT detection of a new fast X-ray transient
  80. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  81. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  82. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  83. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  84. Fermi GBM triggers 736668287/240506253 and 736669277/240506265 are not GRBs
  85. LIGO/Virgo/KAGRA S240505av: Updated Sky localization and EM Bright Classification
  86. Fermi trigger No 736564880: Global MASTER-Net observations report
  87. LIGO/Virgo/KAGRA S240505av: Identification of a GW compact binary merger candidate
  88. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  89. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  90. Fermi trigger No 736461232: Global MASTER-Net observations report
  91. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  92. Fermi GRB 240504A: Global MASTER-Net observations report
  93. Fermi trigger No 736472503: Global MASTER-Net observations report
  94. GW170817: VLA observations at ~5.5 yrs since merger
  95. GRB 240503A: AstroSat CZTI detection
  96. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  97. GRB 240504A: Fermi GBM Final Real-time Localization
  98. Fermi trigger No 736387941: Global MASTER-Net observations report
  99. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  100. GRB 240502A: GOTO optical upper limit

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