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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"

28306 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. GRB 241120A: Mondy and AbAO optical observations
  6. EP241119a: Optical upper limits with Kinder observations
  7. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  8. EP241119a: GIT optical upper limits
  9. EP241119a : J-band observations with WINTER
  10. GRB 241120A: Fermi GBM Observation
  11. EP241119a: EP detection of a fast X-ray transient
  12. GRB241120A: a long GRB detected by INTEGRAL
  13. GRB 241112B: Mephisto further optical observations
  14. GRB 241030A: J-band observations
  15. GRB 241115a: PRIME near-infrared upper limits
  16. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  17. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  18. GRB 241115B: Fermi GBM Observation
  19. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  20. Updates to IceCube realtime alert system for muon tracks
  21. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  22. GRB 241117A: Fermi GBM Detection
  23. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  24. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  25. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  26. GRB 241115C: Fermi GBM Observation
  27. GRB 241115A: Swift-XRT afterglow detection
  28. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  29. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  30. GRB 241115A: Mephisto upper limits
  31. GRB 241113B: Mephisto upper limits
  32. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  33. GRB 241115D / EP 241115a: SVOM/GRM observation
  34. EP241113a: Swift XRT weak detection
  35. GRB 241115A: Fermi GBM Observation
  36. GRB 241115A: LCOGT Optical Upper Limits
  37. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  38. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  39. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  40. EP241115a: EP detection of a fast X-ray transient
  41. Swift GRB 241115A: Global MASTER-Net observations report
  42. Fermi GRB 241115A: Global MASTER-Net observations report
  43. GRB 241115A: Swift detection of a burst
  44. EP 241113a: LBT possible optical counterpart
  45. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  46. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  47. GRB 241113A: Swift-BAT refined analysis
  48. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  49. GRB 241113A: PRIME near-infrared upper limits
  50. EP241113a: Global MASTER-Net observations report
  51. GRB 241113B: J-band upper limit from WINTER
  52. GRB 241113A: J-band observations with WINTER
  53. EP241113a : J-band observations with WINTER
  54. GRB 241030A: LCO optical observation
  55. GRB 241113B: Swift-XRT observations
  56. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  57. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  58. EP241113b/GRB 241113B: EP detection of GRB 241113B
  59. Fermi-LAT gamma-ray observations of IceCube-241113A
  60. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  61. GRB 241113A: Swift-XRT refined Analysis
  62. GRB 241113A: Swift/UVOT Detection
  63. GRB 241113A: REM detection of the optical/NIR afterglow
  64. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  65. GRB 241113A: LCO optical observations
  66. GRB 241112B: GMG Optical Upper Limit
  67. GRB 241113A: Enhanced Swift-XRT position
  68. GRB241113A: LCOGT (40-cm) optical counterpart detection
  69. GRB 241113A: Swift detection of a burst with an optical counterpart
  70. SVOM/GRM detection of a short burst from SGR 1E1841-045
  71. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  72. GRB 241112B: AbAO optical upper limit
  73. GRB 241107A: GROWTH-India telescope optical upper limit
  74. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  75. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  76. GRB 241112B: Swift-XRT afterglow detection
  77. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  78. GRB 241112B: Mephisto optical upper limits
  79. GRB 241112B: GOTO optical upper limits
  80. GRB 241107A: INTEGRAL IBIS localization
  81. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  82. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  83. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  84. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  85. IPN triangulation of GRB 241107A (short/hard)
  86. GRB 241025C: VZLUSAT-2 detection
  87. GRB 241025A: VZLUSAT-2 detection
  88. GRB 241018A: cubesat Avion detection
  89. GRB 241030B: TESS detection of optical counterpart
  90. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  91. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  92. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  94. Integral GRB241109.89: Global MASTER-Net observations report
  95. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  96. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  97. EP241107a: AbAO optical upper limit
  98. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  99. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  100. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification

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