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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"

23614 results found.

  1. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  2. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  3. GRB 240914A: Swift-XRT observations
  4. GRB 240910A: SVOM/VT optical observations
  5. EP240913a: NOT optical upper limits
  6. EP240913a: JinShan optical upper limits
  7. EP240913a: ESO-NTT optical observations
  8. GRB 240914A: ESO-NTT optical observations
  9. GRB 240905E: further NOT optical observations
  10. EP240913a: EP-WXT detection of a fast X-ray transient
  11. GRB 240911A: LCO optical observations
  12. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  13. GRB 240912A: Swift/UVOT Detection
  14. GRB 240911A: Swift-XRT observations
  15. GRB 240912A: J-band observations with WINTER
  16. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  17. GRB 240912A: Enhanced Swift-XRT position
  18. GRB 240912A: Redshift from OSIRIS+/GTC
  19. Fast X-ray Transient EP240801a: GMRT radio observations
  20. GRB 240910A: Redshift from OSIRIS+/GTC
  21. GRB 240912A: Swift detection of a burst with an optical counterpart
  22. GRB 240910A: JinShan optical observations
  23. IPN triangulation of GRB 240905B (short)
  24. GRB 240825A: 7DT Optical Upper Limit
  25. GRB 240905E: SVOM/VT optical observations
  26. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  28. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  29. GRB 240910A: SVOM/GRM observation
  30. EP240908a: Mondy and AbAO follow-up observations
  31. EP240908a: TRT optical upper limit
  32. EP240908a: EP detection of a fast X-ray transient
  33. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  34. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  35. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  36. GRB 240905E: GIT optical upper limit
  37. GRB 240905B: Swift-XRT observations
  38. GRB 240905E: Gaoyazi/GOT optical upper limits
  39. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  40. GRB 240905B: Fermi-LAT detection
  41. GRB 240905E: J-band observations with WINTER
  42. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  43. GRB 240905E: AKO Optical Upper Limit
  44. GRB 240905E: SVOM/C-GFT optical upper limit
  45. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  46. GRB 240905E: NOT optical upper limits
  47. GRB 240905E: REM optical/NIR upper limits
  48. GRB 240902B: AstroSat CZTI detection of a long burst
  49. GRB 240905E: LCOGT Optical Upper Limit
  50. GRB 240905E: Swift/UVOT Upper Limits
  51. GRB 240905E: SAO RAS optical upper limit
  52. GRB 240905E: Nanshan/HMT optical upper limit
  53. GRB 240905E: Swift detection of a burst
  54. GRB 240819A: Optical upper limits from TESS
  55. GRB 240904A: Swift detection of a burst
  56. LIGO/Virgo/KAGRA S240902bq: Identification of a GW compact binary merger candidate
  57. GRB 240825A: MeerLICHT afterglow detection
  58. GRB 240828A: SAO RAS AS-500(2) optical observations
  59. GRB 240825A: TSHAO Optical Upper Limit
  60. GRB240828B: REM optical/NIR upper limits
  61. GRB 240828B: AbAO optical upper limit
  62. GRB 240825A: SOAR observations
  63. GRB 240828B: Mephisto optical upper limit
  64. GRB 240828B: GRANDMA Optical Upper Limit
  65. LIGO/Virgo/KAGRA S240830gn: Updated Sky localization and EM Bright Classification
  66. LIGO/Virgo/KAGRA S240830gn: Identification of a GW compact binary merger candidate
  67. GRB 240825A: MeerKAT detection
  68. GRB 240828B: J-band upper limit from WINTER
  69. GRB 240828B: GMG Optical Upper Limit
  70. GRB 240828B: SVOM/C-GFT optical upper limit
  71. GRB 240828B: SAO RAS optical upper limit
  72. GRB 240828A: SAO RAS optical observations
  73. GRB 240629A: First GRB Detected by BurstCube
  74. GRB 240828A: KAIT Optical Afterglow Candidate
  75. GRB 240825A: SVOM/VT optical detection
  76. GRB 240828A: Swift-XRT afterglow detection
  77. GRB 240825A: further SAO RAS optical observations
  78. GRB 240825A: iTelescope optical observations
  79. GRB 240828B: Swift-XRT afterglow detection
  80. GRB 240829A: Swift detection of a burst
  81. GRB 240828A: AstroSat CZTI detection of a long burst
  82. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  83. GRB 240819A as a likely X-Ray Flash
  84. GRB 240821A: PRIME near-infrared observations
  85. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  86. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  87. GRB 240825A: SAO RAS optical observations
  88. GRB 240824A: GIT optical upper limit
  89. GRB 240819A: Swift afterglow confirmation
  90. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  91. GRB 240825A: GMG Continued Optical Observation on the Second Night
  92. GRB 240825A: PRIME near-infrared detection
  93. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  94. GRB 240825A: AstroSat CZTI detection of the long bright burst
  95. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  96. GRB 240825A: Swift/UVOT Detection
  97. GRB 240825A: REM detection of the optical/NIR afterglow
  98. GRB 240825A: Montarrenti Observatory optical observations
  99. GRB 240825A: Enhanced Swift-XRT position
  100. GRB 240825A: MASTER optical counterpart observation

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