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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"

28286 results found.

  1. GRB 241115a: PRIME near-infrared upper limits
  2. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  3. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  4. GRB 241115B: Fermi GBM Observation
  5. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  6. Updates to IceCube realtime alert system for muon tracks
  7. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  8. GRB 241117A: Fermi GBM Detection
  9. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  10. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  11. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  12. GRB 241115C: Fermi GBM Observation
  13. GRB 241115A: Swift-XRT afterglow detection
  14. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  15. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  16. GRB 241115A: Mephisto upper limits
  17. GRB 241113B: Mephisto upper limits
  18. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  19. GRB 241115D / EP 241115a: SVOM/GRM observation
  20. EP241113a: Swift XRT weak detection
  21. GRB 241115A: Fermi GBM Observation
  22. GRB 241115A: LCOGT Optical Upper Limits
  23. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  24. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  25. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  26. EP241115a: EP detection of a fast X-ray transient
  27. Swift GRB 241115A: Global MASTER-Net observations report
  28. Fermi GRB 241115A: Global MASTER-Net observations report
  29. GRB 241115A: Swift detection of a burst
  30. EP 241113a: LBT possible optical counterpart
  31. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  32. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  33. GRB 241113A: Swift-BAT refined analysis
  34. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  35. GRB 241113A: PRIME near-infrared upper limits
  36. EP241113a: Global MASTER-Net observations report
  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. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  43. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  44. EP241113b/GRB 241113B: EP detection of GRB 241113B
  45. Fermi-LAT gamma-ray observations of IceCube-241113A
  46. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  47. GRB 241113A: Swift-XRT refined Analysis
  48. GRB 241113A: Swift/UVOT Detection
  49. GRB 241113A: REM detection of the optical/NIR afterglow
  50. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  51. GRB 241113A: LCO optical observations
  52. GRB 241112B: GMG Optical Upper Limit
  53. GRB 241113A: Enhanced Swift-XRT position
  54. GRB241113A: LCOGT (40-cm) optical counterpart detection
  55. GRB 241113A: Swift detection of a burst with an optical counterpart
  56. SVOM/GRM detection of a short burst from SGR 1E1841-045
  57. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  58. GRB 241112B: AbAO optical upper limit
  59. GRB 241107A: GROWTH-India telescope optical upper limit
  60. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  61. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  62. GRB 241112B: Swift-XRT afterglow detection
  63. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  64. GRB 241112B: Mephisto optical upper limits
  65. GRB 241112B: GOTO optical upper limits
  66. GRB 241107A: INTEGRAL IBIS localization
  67. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  68. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  69. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  70. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  71. IPN triangulation of GRB 241107A (short/hard)
  72. GRB 241025C: VZLUSAT-2 detection
  73. GRB 241025A: VZLUSAT-2 detection
  74. GRB 241018A: cubesat Avion detection
  75. GRB 241030B: TESS detection of optical counterpart
  76. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  77. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  78. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  80. Integral GRB241109.89: Global MASTER-Net observations report
  81. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  82. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  83. EP241107a: AbAO optical upper limit
  84. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  85. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  86. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  87. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  88. EP241109a: confirmation of a stellar flare by BOOTES-7
  89. GRB 241108A: Swift-XRT observations
  90. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  91. EP241107a: KAIT optical observations
  92. GRB 241030A: TESS observations
  93. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  94. EP241107a: Kinder optical follow-up observations
  95. GRB 241025A: radio detection with the VLA
  96. EP241107a: AKO Optical Afterglow Follow-Up Observations
  97. EP241107a: GSP detects optical counterpart
  98. GRB 241105A: SVOM/GRM observation
  99. EP241107a: OHP/T193 photometric and spectroscopic observations
  100. GRB 241105a: PRIME near-infrared upper limits

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