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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"

5528 results found.

  1. Fermi trigger No 737788024: Global MASTER-Net observations report
  2. Fermi GRB 240517A: Global MASTER-Net observations report
  3. IPN triangulation of GRB 240514B (short)
  4. GRB 240516A: AstroSat CZTI detection
  5. GRB 240516A: Fermi GBM Observation
  6. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  7. Fermi trigger No 737523389: Global MASTER-Net observations report
  8. GRB 240516A: Swift detection of a burst
  9. Swift GRB240516.15: Global MASTER-Net observations report
  10. MAXI GRB240514.78: Global MASTER-Net observations report
  11. GRB 240514B: GRBAlpha detection
  12. GRB 240514B: Fermi GBM Detection
  13. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  14. GRB 240514B: Fermi GBM Final Real-time Localization
  15. LAT GRB240513.31: Global MASTER-Net observations report
  16. Fermi trigger No 737277727: Global MASTER-Net observations report
  17. Fermi trigger No 737247400: Global MASTER-Net observations report
  18. GRB 240511A : MITSuME Akeno optical upper limits
  19. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  21. Fermi trigger No 736564880: Global MASTER-Net observations report
  22. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  23. GRB 240503A: AstroSat CZTI detection
  24. Fermi trigger No 736387941: Global MASTER-Net observations report
  25. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  26. Fermi trigger No 736379109: Global MASTER-Net observations report
  27. GRB 240502C: GOTO possible optical counterpart candidates
  28. Fermi GRB 240502B: Global MASTER-Net observations report
  29. Fermi GRB 240502A: Global MASTER-Net observations report
  30. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  31. Fermi GRB 240501A: Global MASTER-Net observations report
  32. Fermi trigger No 736197684: Global MASTER-Net observations report
  33. GRB 240408B: VZLUSAT-2 detection
  34. LIGO/Virgo/KAGRA S240501an: Identification of a GW compact binary merger candidate
  35. LIGO/Virgo/KAGRA S240422ed: GRANDMA Optical Upper Limits for EP240426a
  36. LIGO/Virgo/KAGRA S240422ed: Continued Magellan Observations
  37. LIGO/Virgo/KAGRA S240426s: Identification of a GW compact binary merger candidate
  38. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility contuinued observations of S240422ed and candidate analysis
  39. S240422ed: MeerLICHT/BlackGEM photometry on AT2024hfx and archival ZTF detection
  40. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  41. LIGO/Virgo/KAGRA S240422ed: Additional DECam GW-MMADS Candidates from the first two nights of observations
  42. LIGO/Virgo/KAGRA S240422ed: Archival BlackGEM/MeerLICHT detections of AT 2024hdr & AT 2024hdq
  43. LIGO/Virgo/KAGRA S240422ed: No significant counterpart candidates in HAWC observations
  44. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA/FRAM Observations
  45. LIGO/Virgo/KAGRA S240422ed: ATCA follow-up of candidate counterparts
  46. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  47. LIGO/Virgo/KAGRA S240422ed: DECam GW-MMADS Candidates
  48. IceCube Alert 240424.08: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S240422ed: SAGUARO upper limits from CSS
  50. LIGO/Virgo/KAGRA S240422ed: Subaru/MOIRCS near-infrared observations by J-GEM Collaboration
  51. LIGO/Virgo/KAGRA S240422ed: No Counterparts in DDOTI/OAN Optical Observations
  52. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility observations and candidates
  53. LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam observations
  54. LIGO/Virgo/KAGRA S240422ed: Magellan Observations
  55. LIGO/Virgo/KAGRA S240422ed: Updated NED Galaxies in the Localization Volume
  56. LIGO/Virgo/Kagra S240422ed: NED Galaxies in the Localization Volume
  57. Fermi GRB 240422A: Global MASTER-Net observations report
  58. Fermi trigger No 735280430: Global MASTER-Net observations report
  59. Fermi trigger No 735089036: Global MASTER-Net observations report
  60. Fermi GRB 240417A: Global MASTER-Net observations report
  61. Improved IPN triangulation of GRB 240411A
  62. GRB 240415A: SAO RAS optical observations
  63. Fermi GRB 240415A: Global MASTER-Net observations report
  64. Fermi trigger No 734754044: Global MASTER-Net observations report
  65. IPN triangulation of GRB 240411A
  66. GRB 240414A : OHP/T193 redshift determination
  67. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  68. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  69. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  70. IceCube Alert 240412.23: Global MASTER-Net observations report
  71. GRB 240408B: GRBAlpha detection
  72. EP240408A: MASTER optical observations
  73. Swift Trigger 1220736: detection of 4U 1543-62.
  74. Fermi GRB 240408A: Global MASTER-Net observations report
  75. Fermi GRB 240407A: Global MASTER-Net observations report
  76. Fermi-LAT gamma-ray observations of IceCube-240327B
  77. Fermi-LAT gamma-ray observations of IceCube-240327A
  78. GRB 240331A: GRBAlpha detection
  79. GRB 240403B: Glowbug gamma-ray detection
  80. GRB 240403A: Glowbug gamma-ray detection
  81. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  82. GRB 240403A: Fermi GBM Detection
  83. LXT 240402A: MASTER optical observations with AGN in error-box
  84. GRB 240402B: GWAC-F50A optical upper limit
  85. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  86. Fermi trigger No 733808041: Global MASTER-Net observations report
  87. Fermi GRB 240402A: Global MASTER-Net observations report
  88. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  89. EP240331A: MASTER optical observations
  90. Transient EP240315a: J-band observations of AT2024eju with WIRC
  91. IceCube-240327B: Upper limits from a search for additional neutrino events in IceCube
  92. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  93. GRB 240329A: Glowbug gamma-ray detection
  94. GRB 240324A: AstroSat CZTI detection of a short burst
  95. GRB 240331A: AstroSat CZTI detection
  96. GRB 240329A: AstroSat CZTI detection
  97. GRB 240329A: GRBAlpha detection
  98. Fermi trigger No 733366352: Global MASTER-Net observations report
  99. Fermi GRB 240329A: Global MASTER-Net observations report
  100. Fermi GRB 240328B: Global MASTER-Net observations report

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