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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"

45813 results found.

  1. GRB 241209B: GRBAlpha detection
  2. GRB 241206C: GRBAlpha detection
  3. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  4. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  5. GRB 241211A: Fermi GBM Final Real-time Localization
  6. GRB 241129A: Fermi GBM Observation
  7. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  8. GRB 241209D: REM optical/NIR upper limits
  9. Konus-Wind detection of GRB 241209D
  10. GRB 241209B: Swift-XRT afterglow detection
  11. GRB 241209C: Fermi GBM Observation
  12. GRB 241209A: Swift-XRT refined Analysis
  13. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  14. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  15. EP241208a: Optical upper limit with Kinder observations
  16. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  17. GRB 241209D: AstroSat CZTI detection
  18. GRB 241209A: EP-FXT follow-up observations
  19. GRB 241209B: SVOM/VT afterglow detection
  20. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  21. EP241208a: Global MASTER-Net observations report
  22. EP241208a: EP-FXT follow-up observations
  23. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  24. Fermi trigger No 755485387: Global MASTER-Net observations report
  25. GRB 241207B: Fermi GBM Observation
  26. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  27. GRB 241209D: Swift-XRT refined Analysis
  28. GRB 241209D: Fermi GBM Observation
  29. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  30. GRB 241209D: COLIBRÍ detection of the afterglow
  31. GRB 241209A: COLIBRÍ Optical Upper Limit
  32. Fermi GRB 241209D: Global MASTER-Net observations report
  33. GRB 241209A: Fermi GBM Observation
  34. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  35. GRB 241209A: GRANDMA/TAROT upper limit
  36. GRB 241209B: BOOTES-5 optical upper limit
  37. Swift GRB 241209D: Global MASTER-Net observations report
  38. Fermi GRB 241209C: Global MASTER-Net observations report
  39. Fermi GRB 241209E: Global MASTER-Net observations report
  40. GRB 241209E: Fermi GBM Final Real-time Localization
  41. GRB 241209B: Swift ToO observations
  42. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  43. GRB 241209A: REM optical/NIR observations
  44. GRB 241209D: Enhanced Swift-XRT position
  45. GRB 241209C: AstroSat CZTI detection
  46. GRB 241209D: Swift detection of a burst
  47. GRB 241209D: Fermi GBM Final Real-time Localization
  48. GRB 241209A: VLT/X-shooter spectroscopy
  49. GRB 241209A: Enhanced Swift-XRT position
  50. GRB 241114B: cubesat Avion detection
  51. GRB 241209A: VLT optical observations
  52. Fermi GRB 241209A: Global MASTER-Net observations report
  53. GRB 241209C: Fermi GBM Final Real-time Localization
  54. GRB 241209A: GOTO optical upper limits
  55. EP241206a: 1.5m OSN optical limit
  56. GRB 241209A: Prompt enhanced Swift-XRT position
  57. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  58. EP241208a: EP detection of a fast X-ray transient
  59. GRB 241209A: Swift detection of a short burst
  60. Swift GRB241209.23: Global MASTER-Net observations report
  61. GRB 241209A: Fermi GBM Final Real-time Localization
  62. Fermi GRB 241207B: Global MASTER-Net observations report
  63. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  64. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  65. GRB 241201A: AstroSat CZTI detection
  66. GRB 241206A: DDOTI Upper Limit on the Afterglow
  67. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  68. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  69. EP241206a: BOOTES Global Network optical limits
  70. GRB 241207C: MASTER optical observations
  71. Fermi trigger No 755225799: Global MASTER-Net observations report
  72. GRB 241207C: Tiled Swift observations
  73. GRB 241207C: MAXI/GSC detection
  74. GRB 241207B: Fermi GBM Final Real-time Localization
  75. Fermi trigger No 755277791: Global MASTER-Net observations report
  76. Fermi GRB 241207A: Global MASTER-Net observations report
  77. EP241206a: Global MASTER-Net observations report
  78. EP241206a: EP detection of a fast X-ray transient
  79. GRB 241206A: Fermi GBM observation
  80. GRB 241206C: SVOM/GRM observation of a likely short burst
  81. GRB 241207A: Fermi GBM Final Real-time Localization
  82. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  83. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  84. GRB 241206B: GWAC-F50A optical upper limit
  85. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  86. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  87. Fermi GRB 241206A: Global MASTER-Net observations report
  88. GRB 241206A: Fermi GBM Final Real-time Localization
  89. EP241201a: 1.6m Mephisto Optical Upper Limits
  90. GRB 241204A: COLIBRÍ Optical Upper Limit
  91. EP241202b: KAIT optical upper limit
  92. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  93. GRB 241204A: DDOTI Upper Limits on the Afterglow
  94. GRB 241204A: Fermi GBM Observation
  95. Fermi GRB 241204A: Global MASTER-Net observations report
  96. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  97. GRB 241128A : RAPAS follow-up observations
  98. GRB 241201A: GRBAlpha detection
  99. GRB 241204A: Fermi-LAT detection
  100. EP241202b: Upper limits from Fermi-GBM Observations

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