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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"

32713 results found.

  1. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  2. Konus-Wind detection of GRB 241117A
  3. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  4. GRB 241105A: ATCA radio detection
  5. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  6. IPN triangulation of GRB 241117A
  7. GRB 241026A: VIRT Optical Upper Limit
  8. GRB 241025A: VIRT Optical Upper Limit
  9. Konus-Wind detection of GRB 241120A
  10. GRB241120A: OHP/T193 optical observations
  11. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  12. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  13. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  14. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  15. GRB 241120A: Mondy and AbAO optical observations
  16. EP241119a: Optical upper limits with Kinder observations
  17. EP241119a: GIT optical upper limits
  18. GRB 241113A: Possible ATCA Radio detection
  19. EP241119a : J-band observations with WINTER
  20. GRB 241120A: Fermi GBM Observation
  21. EP241119a: Global MASTER-Net observations report
  22. GRB241120A: a long GRB detected by INTEGRAL
  23. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  24. GRB 241112B: Mephisto further optical observations
  25. GRB 241030A: J-band observations
  26. GRB 241115a: PRIME near-infrared upper limits
  27. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  28. GRB 241115B: Fermi GBM Observation
  29. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  30. Fermi GRB 241118A: Global MASTER-Net observations report
  31. Updates to IceCube realtime alert system for muon tracks
  32. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  33. Fermi GRB 241117B: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  35. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  36. Fermi GRB 241117A: Global MASTER-Net observations report
  37. GRB 241115C: Fermi GBM Observation
  38. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  39. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  40. GRB 241115A: Mephisto upper limits
  41. GRB 241113B: Mephisto upper limits
  42. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  43. GRB 241115D / EP 241115a: SVOM/GRM observation
  44. The EP-WXT trigger 01709120856 is likely a flaring star
  45. EP241113a: Swift XRT weak detection
  46. GRB 241115A: Fermi GBM Observation
  47. GRB 241115A: LCOGT Optical Upper Limits
  48. Fermi GRB 241115B: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  50. EP241115a: Global MASTER-Net observations report
  51. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  52. EP241113a: No Detection in Fermi-GBM Observations
  53. Swift GRB 241115A: Global MASTER-Net observations report
  54. Fermi GRB 241115A: Global MASTER-Net observations report
  55. EP 241113a: LBT possible optical counterpart
  56. GRB 241113B: KAIT Optical Afterglow Candidate
  57. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  58. GRB 241113A: Swift-BAT refined analysis
  59. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  60. GRB 241113A: PRIME near-infrared upper limits
  61. Fermi GRB 241114A: Global MASTER-Net observations report
  62. EP241113a: Global MASTER-Net observations report
  63. GRB 241113B: J-band upper limit from WINTER
  64. GRB 241113A: J-band observations with WINTER
  65. EP241113a : J-band observations with WINTER
  66. GRB 241030A: LCO optical observation
  67. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  68. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  69. GRB 241113A: KAIT optical observations
  70. EP241113b: Global MASTER-Net observations report
  71. EP241113b/GRB 241113B: EP detection of GRB 241113B
  72. Fermi-LAT gamma-ray observations of IceCube-241113A
  73. GRB 241113B: SVOM/GRM observation
  74. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  75. EP241107a: SOAR upper limits
  76. GRB 241113A: Swift/UVOT Detection
  77. GRB 241113A: REM detection of the optical/NIR afterglow
  78. Konus-Wind detection of GRB 241107A (short/hard)
  79. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  80. GRB 241113B: Swift ToO observations
  81. GRB 241113A: LCO optical observations
  82. GRB 241112B: GMG Optical Upper Limit
  83. GRB241113A: LCOGT (40-cm) optical counterpart detection
  84. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  85. SVOM/GRM detection of a short burst from SGR 1E1841-045
  86. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  87. GRB 241105A: ATCA Radio Upper Limits
  88. GRB 241112B: AbAO optical upper limit
  89. GRB 241107A: GROWTH-India telescope optical upper limit
  90. Fermi GRB 241112A: Global MASTER-Net observations report
  91. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  92. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  93. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  94. GRB 241112B: SVOM/GRM observation
  95. GRB 241112B: SVOM/VT afterglow detection
  96. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  97. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  98. GRB 241112B: Mephisto optical upper limits
  99. GRB 241112B: GOTO optical upper limits
  100. GRB 241112B: Swift ToO observations

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