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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"

22208 results found.

  1. EP241217A: LCO optical observations
  2. EP241217a: Gemini-North detection of the likely optical counterpart
  3. EP241217a: EP detection of an X-ray transient
  4. EP241107a: VLA Radio Observation
  5. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  6. GRB 241215A: Mondy AZT-33IK optical observations
  7. GRB 241212A: Swift-XRT observations
  8. GRB 241215A: Nanshan/HMT optical upper limit
  9. GRB 241215A: Montarrenti Observatory optical upper limit
  10. Integral GRB241215.58: Global MASTER-Net observations report
  11. GRB 241213B: Swift-XRT observations
  12. GRB 241213A: SVOM/VT optical candidate
  13. GRB 241213B: Tiled Swift observations
  14. GRB 241213A: Swift/UVOT Upper Limits
  15. EP241208a: NOT optical upper limits
  16. GRB 241212A: Swift ToO observations
  17. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  18. GRB 241213A: REM optical/NIR upper limits
  19. GRB241212A: OHP/T193 optical observations
  20. GRB 241213A: SAO RAS optical upper limit
  21. Swift GRB 241213A: Global MASTER-Net observations report
  22. GRB 241212A : SVOM/VT bright optical afterglow
  23. GRB 241209B: GRANDMA/TRT upper limit
  24. GRB 241207A: TSHAO Zeiss-1000 optical observations
  25. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  26. GRB 241209A: Chandra X-ray Detection
  27. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  28. GRB 241209D: REM optical/NIR upper limits
  29. GRB 241209B: Swift-XRT afterglow detection
  30. EP241208a: Optical upper limit with Kinder observations
  31. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  32. GRB 241209A: EP-FXT follow-up observations
  33. GRB 241209B: SVOM/VT afterglow detection
  34. EP241208a: Global MASTER-Net observations report
  35. EP241208a: EP-FXT follow-up observations
  36. Fermi trigger No 755485387: Global MASTER-Net observations report
  37. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  38. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  39. GRB 241209D: COLIBRÍ detection of the afterglow
  40. GRB 241209A: COLIBRÍ Optical Upper Limit
  41. Fermi GRB 241209D: Global MASTER-Net observations report
  42. GRB 241209A: Fermi GBM Observation
  43. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  44. GRB 241209A: GRANDMA/TAROT 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 241209B: Swift ToO observations
  49. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  50. GRB 241209A: REM optical/NIR observations
  51. GRB 241209A: VLT/X-shooter spectroscopy
  52. GRB 241209A: VLT optical observations
  53. Fermi GRB 241209A: Global MASTER-Net observations report
  54. GRB 241209A: GOTO optical upper limits
  55. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  56. EP241208a: EP detection of a fast X-ray transient
  57. Swift GRB241209.23: Global MASTER-Net observations report
  58. Fermi GRB 241207B: Global MASTER-Net observations report
  59. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  60. GRB 241206A: DDOTI Upper Limit on the Afterglow
  61. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  62. EP241206a: BOOTES Global Network optical limits
  63. GRB 241207C: MASTER optical observations
  64. Fermi trigger No 755225799: Global MASTER-Net observations report
  65. GRB 241207C: Tiled Swift observations
  66. Fermi trigger No 755277791: Global MASTER-Net observations report
  67. Fermi GRB 241207A: Global MASTER-Net observations report
  68. EP241206a: Global MASTER-Net observations report
  69. EP241206a: EP detection of a fast X-ray transient
  70. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  71. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  72. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  73. Fermi GRB 241206A: Global MASTER-Net observations report
  74. GRB 241204A: COLIBRÍ Optical Upper Limit
  75. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  76. GRB 241204A: DDOTI Upper Limits on the Afterglow
  77. Fermi GRB 241204A: Global MASTER-Net observations report
  78. GRB 241128A : RAPAS follow-up observations
  79. EP241202b: Upper limits from Fermi-GBM Observations
  80. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  81. EP241202b: Kinder optical counterpart candidate
  82. EP241201a: EP-FXT follow-up observations
  83. EP241202b: Global MASTER-Net observations report
  84. EP241202b: EP detection of a fast X-ray transient
  85. EP241201a: NOT optical observations
  86. GRB 241128A: Swift/UVOT Upper Limits
  87. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  88. EP241201a: Kinder optical counterpart candidate
  89. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  90. EP241201a: Global MASTER-Net observations report
  91. EP241201a: EP detection of a fast X-ray transient
  92. EP241126a: SOAR observations of the optical counterpart
  93. Fermi GRB 241201A: Global MASTER-Net observations report
  94. EP241126a: 1.6m Mephisto Optical Upper Limits
  95. Fermi trigger No 754701230: Global MASTER-Net observations report
  96. Konus-Wind detection of GRB 241114B
  97. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  98. EP241126a: NOT optical observations
  99. GRB 241127A: PRIME near-infrared detection
  100. GRB 241128A: Mondy optical observations

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