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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"

28300 results found.

  1. GRB 240825A: LCO optical observations
  2. GRB 240824B: KAIT optical upper limit
  3. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  4. GRB 240824B: Fermi GBM Observation
  5. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  6. GRB 240824B: NOT optical upper limit
  7. GRB 240825A: GMG Optical Observation
  8. GRB 240825A: 1.6m Mephisto multi-band detection
  9. GRB 240825A: AKO Optical Afterglow Detection
  10. GRB 240825A: Skynet Optical Afterglow observations
  11. GRB 240825A: Nanshan/HMT optical afterglow observations
  12. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  13. GRB 240824A: Swift-BAT refined analysis
  14. GRB 240824A: SVOM/C-GFT optical upper limit
  15. GRB 240824B: Swift-XRT afterglow detection
  16. GRB 240824A: Swift-XRT observations
  17. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  18. GRB 240824A: Swift/UVOT Upper Limits
  19. GRB 240821A: Swift/UVOT observations of the XRT sources.
  20. GRB 240824B: MAXI/GSC detection
  21. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  22. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  23. GRB 240824A: Skynet Optical Afterglow Discovery
  24. GRB 240824A: Swift detection of a burst
  25. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  26. GRB 240821A: Colibri Optical Upper Limit
  27. EP240820a: PRIME J-band Observations
  28. GRB 240821A: Swift-XRT observations
  29. GRB 240822A: AstroSat CZTI detection of a short burst
  30. GRB 240821A: REM optical/NIR upper limits
  31. GRB 240821A: LCO optical observations
  32. GRB 240821A: JinShan optical upper limits
  33. GRB 240809A: Mondy and AbAO Optical Observations
  34. GRB 240821A: GMG Optical Upper Limit
  35. Fermi GRB 240821A: Global MASTER-Net observations report
  36. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  37. GRB 240821A: Fermi GBM Observation
  38. Fermi trigger No 745925274: Global MASTER-Net observations report
  39. Fermi trigger No 745935375: Global MASTER-Net observations report
  40. GRB240821A: EIRSAT-1 GMOD Detection
  41. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  42. GRB 240821A: SVOM/GRM observation
  43. GRB 240821A: SVOM/GRM observation
  44. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  45. Fermi trigger No 745866488: Global MASTER-Net observations report
  46. GRB 240821A: BALROG localization (Fermi Trigger 745958167 / GRB 240821775)
  47. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  48. GRB 240819A: Swift-XRT observations
  49. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  50. EP240820a: TRT optical upper limit
  51. EP240820a: EP detection of a fast X-ray transient
  52. EP240816a: PRIME upper limits
  53. Fermi trigger No 745873283: Global MASTER-Net observations report
  54. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  55. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  56. EP240816b: Liverpool Telescope optical follow-up observations
  57. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  58. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  59. EP240816b: TRT optical upper limit
  60. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  61. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  62. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  63. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  65. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  66. GRB 240810A: SVOM/GRM observation
  67. GRB 240809A : RAPAS follow-up observations
  68. GRB 240811A: Swift-BAT refined analysis
  69. GRB 240809A: Swift-BAT refined analysis
  70. EP240807a: PRIME H-band upper limits
  71. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube
  72. GRB 240811A: Bassano Bresciano Observatory upper limit
  73. GRB 240811A: Swift-XRT refined Analysis
  74. GRB 240811A: Swift/UVOT Upper Limits
  75. EP240801a: Assy-Turgen optical observations
  76. Fermi GRB 240810A: Global MASTER-Net observations report
  77. GRB 240811A: LCOGT Optical Upper Limit
  78. GRB 240811A: Enhanced Swift-XRT position
  79. GRB 240811A: Upper limits with Mephisto
  80. GRB 240811A: Swift detection of a burst
  81. GRB 240809A: REM detection of the optical afterglow
  82. GRB 240809A: Bassano Bresciano Observatory optical observations
  83. Fermi-LAT gamma-ray observations of IceCube-240808A
  84. GRB 240809A: GIT afterglow observations
  85. GRB 240809B: MAXI/GSC detection
  86. GRB 240809A: Swift/UVOT Detection
  87. GRB 240809A: Swift-XRT refined Analysis
  88. IPN triangulation of GRB 240807A / EP 240807a
  89. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  90. X-ray Transient EP240807a: PRIME near-infrared upper limits
  91. GRB 240809A: JinShan optical observations
  92. GRB 240809A: Enhanced Swift-XRT position
  93. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  94. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  95. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  96. EP EP240806a: Global MASTER-Net observations report
  97. GRB 240710B: VZLUSAT-2 detection
  98. S240807h: Identification of a GW compact binary merger candidate
  99. GRB 240720B: VZLUSAT-2 detection
  100. GRB 240710A: VZLUSAT-2 detection

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