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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').
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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"

21940 results found.

  1. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  2. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  3. GRB 241026A: radio detection with the VLA
  4. EP241125a: Optical upper limit with Kinder observations
  5. EP241125a: EP detection of an X-ray transient
  6. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  7. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  8. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  9. GRB 241120A: GRBAlpha detection
  10. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  11. Konus-Wind detection of GRB 241117A
  12. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  13. IPN triangulation of GRB 241117A
  14. GRB 241026A: VIRT Optical Upper Limit
  15. GRB 241025A: VIRT Optical Upper Limit
  16. GRB241120A: OHP/T193 optical observations
  17. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  18. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  19. GRB 241120A: Mondy and AbAO optical observations
  20. EP241119a: Optical upper limits with Kinder observations
  21. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  22. EP241119a: GIT optical upper limits
  23. EP241119a : J-band observations with WINTER
  24. EP241119a: EP detection of a fast X-ray transient
  25. GRB 241112B: Mephisto further optical observations
  26. GRB 241030A: J-band observations
  27. GRB 241115a: PRIME near-infrared upper limits
  28. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  29. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  30. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  31. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  32. GRB 241115A: Swift-XRT afterglow detection
  33. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  34. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  35. GRB 241115A: Mephisto upper limits
  36. GRB 241113B: Mephisto upper limits
  37. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  38. GRB 241115D / EP 241115a: SVOM/GRM observation
  39. EP241113a: Swift XRT weak detection
  40. GRB 241115A: LCOGT Optical Upper Limits
  41. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  42. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  43. EP241115a: EP detection of a fast X-ray transient
  44. Swift GRB 241115A: Global MASTER-Net observations report
  45. Fermi GRB 241115A: Global MASTER-Net observations report
  46. GRB 241115A: Swift detection of a burst
  47. EP 241113a: LBT possible optical counterpart
  48. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  49. GRB 241113A: PRIME near-infrared upper limits
  50. GRB 241113B: J-band upper limit from WINTER
  51. GRB 241113A: J-band observations with WINTER
  52. EP241113a : J-band observations with WINTER
  53. GRB 241030A: LCO optical observation
  54. GRB 241113B: Swift-XRT observations
  55. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  56. EP241113b/GRB 241113B: EP detection of GRB 241113B
  57. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  58. GRB 241113A: Swift/UVOT Detection
  59. GRB 241113A: REM detection of the optical/NIR afterglow
  60. Konus-Wind detection of GRB 241107A (short/hard)
  61. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  62. GRB 241113A: LCO optical observations
  63. GRB 241112B: GMG Optical Upper Limit
  64. GRB 241113A: Enhanced Swift-XRT position
  65. GRB241113A: LCOGT (40-cm) optical counterpart detection
  66. GRB 241113A: Swift detection of a burst with an optical counterpart
  67. SVOM/GRM detection of a short burst from SGR 1E1841-045
  68. Fermi trigger No 753166198: Global MASTER-Net observations report
  69. GRB 241112B: AbAO optical upper limit
  70. GRB 241107A: GROWTH-India telescope optical upper limit
  71. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  72. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  73. GRB 241112B: Mephisto optical upper limits
  74. GRB 241112B: GOTO optical upper limits
  75. GRB 241107A: INTEGRAL IBIS localization
  76. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  77. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  78. IPN triangulation of GRB 241107A (short/hard)
  79. GRB 241025C: VZLUSAT-2 detection
  80. GRB 241025A: VZLUSAT-2 detection
  81. GRB 241018A: cubesat Avion detection
  82. GRB 241030B: TESS detection of optical counterpart
  83. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  85. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  86. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  87. EP241107a: AbAO optical upper limit
  88. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  89. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  90. EP241109a: confirmation of a stellar flare by BOOTES-7
  91. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  92. EP241107a: KAIT optical observations
  93. GRB 241030A: TESS observations
  94. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  95. EP241107a: Kinder optical follow-up observations
  96. GRB 241025A: radio detection with the VLA
  97. EP241107a: AKO Optical Afterglow Follow-Up Observations
  98. EP241107a: GSP detects optical counterpart
  99. GRB 241105A: SVOM/GRM observation
  100. EP241107a: OHP/T193 photometric and spectroscopic observations

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