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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"

43984 results found.

  1. GRB 241207A: TSHAO Zeiss-1000 optical observations
  2. GRB 241212A: SVOM detection of a bright long burst
  3. GRB 241212A: Fermi GBM Final Real-time Localization
  4. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  5. GRB 241209A: Chandra X-ray Detection
  6. Konus-Wind detection of GRB 241209B
  7. GRB 241207A: EIRSAT-1 GMOD Detection
  8. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  9. GRB 241209B: GRBAlpha detection
  10. GRB 241206C: GRBAlpha detection
  11. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  12. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  13. GRB 241211A: Fermi GBM Final Real-time Localization
  14. GRB 241129A: Fermi GBM Observation
  15. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  16. GRB 241209D: REM optical/NIR upper limits
  17. Konus-Wind detection of GRB 241209D
  18. GRB 241209B: Swift-XRT afterglow detection
  19. GRB 241209C: Fermi GBM Observation
  20. GRB 241209A: Swift-XRT refined Analysis
  21. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  22. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  23. EP241208a: Optical upper limit with Kinder observations
  24. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  25. GRB 241209D: AstroSat CZTI detection
  26. GRB 241209A: EP-FXT follow-up observations
  27. GRB 241209B: SVOM/VT afterglow detection
  28. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  29. EP241208a: Global MASTER-Net observations report
  30. EP241208a: EP-FXT follow-up observations
  31. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  32. Fermi trigger No 755485387: Global MASTER-Net observations report
  33. GRB 241207B: Fermi GBM Observation
  34. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  35. GRB 241209D: Swift-XRT refined Analysis
  36. GRB 241209D: Fermi GBM Observation
  37. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  38. GRB 241209D: COLIBRÍ detection of the afterglow
  39. GRB 241209A: COLIBRÍ Optical Upper Limit
  40. Fermi GRB 241209D: Global MASTER-Net observations report
  41. GRB 241209A: Fermi GBM Observation
  42. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  43. GRB 241209A: GRANDMA/TAROT upper limit
  44. GRB 241209B: BOOTES-5 optical upper limit
  45. Swift GRB 241209D: Global MASTER-Net observations report
  46. Fermi GRB 241209C: Global MASTER-Net observations report
  47. Fermi GRB 241209E: Global MASTER-Net observations report
  48. GRB 241209E: Fermi GBM Final Real-time Localization
  49. GRB 241209B: Swift ToO observations
  50. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  51. GRB 241209A: REM optical/NIR observations
  52. GRB 241209D: Enhanced Swift-XRT position
  53. GRB 241209C: AstroSat CZTI detection
  54. GRB 241209D: Swift detection of a burst
  55. GRB 241209D: Fermi GBM Final Real-time Localization
  56. GRB 241209A: VLT/X-shooter spectroscopy
  57. GRB 241209A: Enhanced Swift-XRT position
  58. GRB 241114B: cubesat Avion detection
  59. GRB 241209A: VLT optical observations
  60. Fermi GRB 241209A: Global MASTER-Net observations report
  61. GRB 241209C: Fermi GBM Final Real-time Localization
  62. GRB 241209A: GOTO optical upper limits
  63. EP241206a: 1.5m OSN optical limit
  64. GRB 241209A: Prompt enhanced Swift-XRT position
  65. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  66. EP241208a: EP detection of a fast X-ray transient
  67. GRB 241209A: Swift detection of a short burst
  68. Swift GRB241209.23: Global MASTER-Net observations report
  69. GRB 241209A: Fermi GBM Final Real-time Localization
  70. Fermi GRB 241207B: Global MASTER-Net observations report
  71. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  72. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  73. GRB 241201A: AstroSat CZTI detection
  74. GRB 241206A: DDOTI Upper Limit on the Afterglow
  75. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  76. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  77. EP241206a: BOOTES Global Network optical limits
  78. GRB 241207C: MASTER optical observations
  79. Fermi trigger No 755225799: Global MASTER-Net observations report
  80. GRB 241207C: Tiled Swift observations
  81. GRB 241207C: MAXI/GSC detection
  82. GRB 241207B: Fermi GBM Final Real-time Localization
  83. Fermi trigger No 755277791: Global MASTER-Net observations report
  84. Fermi GRB 241207A: Global MASTER-Net observations report
  85. EP241206a: Global MASTER-Net observations report
  86. EP241206a: EP detection of a fast X-ray transient
  87. GRB 241206A: Fermi GBM observation
  88. GRB 241206C: SVOM/GRM observation of a likely short burst
  89. GRB 241207A: Fermi GBM Final Real-time Localization
  90. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  91. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  92. GRB 241206B: GWAC-F50A optical upper limit
  93. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  94. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  95. Fermi GRB 241206A: Global MASTER-Net observations report
  96. GRB 241206A: Fermi GBM Final Real-time Localization
  97. EP241201a: 1.6m Mephisto Optical Upper Limits
  98. GRB 241204A: COLIBRÍ Optical Upper Limit
  99. EP241202b: KAIT optical upper limit
  100. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes

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