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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"

21944 results found.

  1. GRB 240825A: SAO RAS optical observations
  2. GRB 240824A: GIT optical upper limit
  3. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  4. GRB 240825A: GMG Continued Optical Observation on the Second Night
  5. GRB 240825A: PRIME near-infrared detection
  6. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  7. GRB 240825A: AKO Optical Follow-Up Observations
  8. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  9. GRB 240825A: Swift/UVOT Detection
  10. GRB 240825A: REM detection of the optical/NIR afterglow
  11. GRB 240825A: Montarrenti Observatory optical observations
  12. GRB 240825A: Enhanced Swift-XRT position
  13. GRB 240825A: Fermi-LAT detection
  14. GRB 240825A: LCO optical observations
  15. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  16. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  17. GRB 240824B: NOT optical upper limit
  18. GRB 240825A: GMG Optical Observation
  19. GRB 240825A: 1.6m Mephisto multi-band detection
  20. GRB 240825A: AKO Optical Afterglow Detection
  21. GRB 240825A: Skynet Optical Afterglow observations
  22. GRB 240825A: Nanshan/HMT optical afterglow observations
  23. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  24. GRB 240824A: SVOM/C-GFT optical upper limit
  25. GRB 240824B: Swift-XRT afterglow detection
  26. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  27. GRB 240824A: Swift/UVOT Upper Limits
  28. GRB 240821A: Swift/UVOT observations of the XRT sources.
  29. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  30. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  31. GRB 240824A: KAIT optical upper limit
  32. GRB 240824A: Skynet Optical Afterglow Discovery
  33. GRB 240824A: Swift detection of a burst
  34. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  35. GRB 240821A: Colibri Optical Upper Limit
  36. EP240820a: PRIME J-band Observations
  37. GRB 240821A: REM optical/NIR upper limits
  38. GRB 240821A: LCO optical observations
  39. GRB 240821A: JinShan optical upper limits
  40. GRB 240809A: Mondy and AbAO Optical Observations
  41. GRB 240821A: GMG Optical Upper Limit
  42. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  43. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  44. EP240820a: TRT optical upper limit
  45. EP240820a: EP detection of a fast X-ray transient
  46. EP240816a: PRIME upper limits
  47. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  48. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  49. EP240816b: Liverpool Telescope optical follow-up observations
  50. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  51. GRB 240814B: GRBAlpha detection
  52. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  53. EP240816b: TRT optical upper limit
  54. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  55. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  56. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  58. EP240807a: PRIME H-band upper limits
  59. GRB 240811A: Bassano Bresciano Observatory upper limit
  60. GRB 240811A: Swift/UVOT Upper Limits
  61. EP240801a: Assy-Turgen optical observations
  62. GRB 240811A: LCOGT Optical Upper Limit
  63. GRB 240811A: Enhanced Swift-XRT position
  64. GRB 240811A: Upper limits with Mephisto
  65. Konus-Wind detection of GRB 240809A
  66. GRB 240811A: Swift detection of a burst
  67. GRB 240809A: REM detection of the optical afterglow
  68. GRB 240809A: Bassano Bresciano Observatory optical observations
  69. GRB 240809A: GIT afterglow observations
  70. GRB 240809A: Swift/UVOT Detection
  71. IPN triangulation of GRB 240807A / EP 240807a
  72. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  73. X-ray Transient EP240807a: PRIME near-infrared upper limits
  74. GRB 240809A: JinShan optical observations
  75. GRB 240809A: Enhanced Swift-XRT position
  76. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  77. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  78. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  79. GRB 240801A: GRBAlpha detection
  80. GRB 240710B: VZLUSAT-2 detection
  81. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  82. S240807h: Identification of a GW compact binary merger candidate
  83. GRB 240720B: VZLUSAT-2 detection
  84. GRB 240710A: VZLUSAT-2 detection
  85. EP240806A: Liverpool Telescope optical follow-up observations
  86. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  87. EP240807a: EP-WXT detection of a fast X-ray transient
  88. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  89. GRB 240805B: GIT optical upper limit
  90. EP240806a: LCOGT optical counterpart detection
  91. Konus-Wind detection of GRB 240802A (EP240802a)
  92. Konus-Wind detection of GRB 240805A
  93. GRB 240805B Bassano Bresciano Observatory upper limit
  94. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  95. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  96. GRB 240626B: VZLUSAT-2 detection
  97. GRB 240624B: VZLUSAT-2 detection
  98. GRB 240619C: VZLUSAT-2 detection
  99. EP 240806A: LCO optical observations
  100. EP240806a: EP-WXT detection of a fast X-ray transient

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