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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"

37576 results found.

  1. GRB 241115A: Fermi GBM Observation
  2. GRB 241115A: LCOGT Optical Upper Limits
  3. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  4. Fermi GRB 241115B: Global MASTER-Net observations report
  5. GRB 241115B: Fermi GBM Final Real-time Localization
  6. EP241113a: No Detection in Fermi-GBM Observations
  7. Swift GRB 241115A: Global MASTER-Net observations report
  8. Fermi GRB 241115A: Global MASTER-Net observations report
  9. GRB 241115A: Swift detection of a burst
  10. GRB 241115A: Fermi GBM Final Real-time Localization
  11. GRB 241113B: KAIT Optical Afterglow Candidate
  12. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  13. GRB 241113A: Swift-BAT refined analysis
  14. GRB 241113A: PRIME near-infrared upper limits
  15. Fermi GRB 241114A: Global MASTER-Net observations report
  16. GRB 241114A: Fermi GBM Final Real-time Localization
  17. GRB 241113B: J-band upper limit from WINTER
  18. GRB 241113A: J-band observations with WINTER
  19. GRB 241030A: LCO optical observation
  20. GRB 241113B: Swift-XRT observations
  21. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  22. GRB 241113A: KAIT optical observations
  23. EP241113b/GRB 241113B: EP detection of GRB 241113B
  24. Fermi-LAT gamma-ray observations of IceCube-241113A
  25. GRB 241113B: SVOM/GRM observation
  26. GRB 241113A: Swift-XRT refined Analysis
  27. GRB 241113A: Swift/UVOT Detection
  28. GRB 241113A: REM detection of the optical/NIR afterglow
  29. Konus-Wind detection of GRB 241107A (short/hard)
  30. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  31. GRB 241113B: Swift ToO observations
  32. GRB 241113A: LCO optical observations
  33. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  34. GRB 241112B: GMG Optical Upper Limit
  35. GRB 241113A: Enhanced Swift-XRT position
  36. GRB241113A: LCOGT (40-cm) optical counterpart detection
  37. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  38. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  39. GRB 241113A: Swift detection of a burst with an optical counterpart
  40. Fermi trigger No 753166198: Global MASTER-Net observations report
  41. GRB 241105A: ATCA Radio Upper Limits
  42. GRB 241112B: AbAO optical upper limit
  43. GRB 241107A: GROWTH-India telescope optical upper limit
  44. Fermi GRB 241112A: Global MASTER-Net observations report
  45. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  46. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  47. GRB 241112B: Swift-XRT afterglow detection
  48. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  49. GRB 241112B: SVOM/GRM observation
  50. GRB 241112B: SVOM/VT afterglow detection
  51. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  52. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  53. GRB 241112B: Mephisto optical upper limits
  54. GRB 241112B: GOTO optical upper limits
  55. GRB 241112B: Swift ToO observations
  56. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  57. GRB 241107A: INTEGRAL IBIS localization
  58. GRB 241112A: Fermi GBM Final Real-time Localization
  59. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  60. IPN triangulation of GRB 241107A (short/hard)
  61. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  62. GRB 241025C: VZLUSAT-2 detection
  63. GRB 241025A: VZLUSAT-2 detection
  64. GRB 241018A: cubesat Avion detection
  65. Fermi trigger No 752990530: Global MASTER-Net observations report
  66. GRB 241111A: Fermi GBM Final Real-time Localization
  67. GRB 241030B: TESS detection of optical counterpart
  68. Fermi trigger No 752878030: Global MASTER-Net observations report
  69. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  70. EP241107a: AbAO optical upper limit
  71. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  72. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  73. GRB 241108A: Swift-XRT observations
  74. EP241107A: MASTER optical observations of xray transient
  75. EP241107a: KAIT optical observations
  76. GRB 241108A: Swift ToO observations
  77. GRB 241030A: TESS observations
  78. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  79. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  80. GRB 241025A: radio detection with the VLA
  81. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241107A: SVOM/GRM detection of a short burst
  83. GRB 241105A: EP-FXT follow-up observations
  84. GRB 241105A: SVOM/GRM observation
  85. GRB 241105a: PRIME near-infrared upper limits
  86. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  87. GRB 241025A: LBT optical observations
  88. GRB241105A: Gemini-South Optical Afterglow Detection
  89. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  90. GRB 241105A: Swift/UVOT Detection
  91. EP241101a: CrAO ZTSH optical observations
  92. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  93. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  94. GRB 241105A: BOOTES-7 optical detection
  95. GRB 241030A: Mondy optical observations
  96. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  97. Konus-Wind detection of GRB 241105A (short with extended emission)
  98. Konus-Wind detection of GRB 241021A
  99. GRB 241105A: SVOM/VT optical afterglow observations
  100. GRB 241105A: Swift-XRT afterglow detection

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