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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"

23611 results found.

  1. GRB 241026A: VIRT Optical Upper Limit
  2. GRB 241025A: VIRT Optical Upper Limit
  3. GRB241120A: OHP/T193 optical observations
  4. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  5. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  6. GRB 241120A: Mondy and AbAO optical observations
  7. EP241119a: Optical upper limits with Kinder observations
  8. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  9. EP241119a: GIT optical upper limits
  10. EP241119a : J-band observations with WINTER
  11. EP241119a: EP detection of a fast X-ray transient
  12. GRB 241112B: Mephisto further optical observations
  13. GRB 241030A: J-band observations
  14. GRB 241115a: PRIME near-infrared upper limits
  15. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  16. Fermi GRB 241118A: Global MASTER-Net observations report
  17. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  18. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  19. GRB 241115A: Swift-XRT afterglow detection
  20. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  21. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  22. GRB 241115A: Mephisto upper limits
  23. GRB 241113B: Mephisto upper limits
  24. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  25. GRB 241115D / EP 241115a: SVOM/GRM observation
  26. The EP-WXT trigger 01709120856 is likely a flaring star
  27. EP241113a: Swift XRT weak detection
  28. GRB 241115A: LCOGT Optical Upper Limits
  29. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  30. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  31. EP241115a: EP detection of a fast X-ray transient
  32. GRB 241115A: Swift detection of a burst
  33. EP 241113a: LBT possible optical counterpart
  34. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  35. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  36. GRB 241113A: PRIME near-infrared upper limits
  37. GRB 241113B: J-band upper limit from WINTER
  38. GRB 241113A: J-band observations with WINTER
  39. EP241113a : J-band observations with WINTER
  40. GRB 241030A: LCO optical observation
  41. GRB 241113B: Swift-XRT observations
  42. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  43. EP241113b/GRB 241113B: EP detection of GRB 241113B
  44. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  45. GRB 241113A: Swift-XRT refined Analysis
  46. GRB 241113A: Swift/UVOT Detection
  47. GRB 241113A: REM detection of the optical/NIR afterglow
  48. Konus-Wind detection of GRB 241107A (short/hard)
  49. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  50. GRB 241113A: LCO optical observations
  51. GRB 241112B: GMG Optical Upper Limit
  52. GRB 241113A: Enhanced Swift-XRT position
  53. GRB241113A: LCOGT (40-cm) optical counterpart detection
  54. GRB 241113A: Swift detection of a burst with an optical counterpart
  55. SVOM/GRM detection of a short burst from SGR 1E1841-045
  56. GRB 241105A: ATCA Radio Upper Limits
  57. GRB 241112B: AbAO optical upper limit
  58. GRB 241107A: GROWTH-India telescope optical upper limit
  59. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  60. GRB 241112B: Swift-XRT afterglow detection
  61. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  62. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  63. GRB 241112B: Mephisto optical upper limits
  64. GRB 241112B: GOTO optical upper limits
  65. GRB 241107A: INTEGRAL IBIS localization
  66. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  67. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  68. IPN triangulation of GRB 241107A (short/hard)
  69. GRB 241018A: cubesat Avion detection
  70. GRB 241030B: TESS detection of optical counterpart
  71. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  72. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  74. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  75. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  76. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  77. EP241107a: AbAO optical upper limit
  78. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  79. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  80. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  81. GRB 241108A: Swift-XRT observations
  82. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  83. EP241107a: KAIT optical observations
  84. GRB 241030A: TESS observations
  85. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  86. EP241107a: Kinder optical follow-up observations
  87. GRB 241025A: radio detection with the VLA
  88. EP241107a: AKO Optical Afterglow Follow-Up Observations
  89. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  90. GRB 241105A: SVOM/GRM observation
  91. EP241107a: OHP/T193 photometric and spectroscopic observations
  92. GRB 241105a: PRIME near-infrared upper limits
  93. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  94. EP241107a: GIT optical observations
  95. EP241107a: SVOM/C-GFT optical observations
  96. EP241107a: AKO Optical Afterglow Detection
  97. GRB 241025A: LBT optical observations
  98. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  99. GRB 241105A: Swift/UVOT Detection
  100. EP241101a: CrAO ZTSH optical observations

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