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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"

32715 results found.

  1. EP241217a: Kinder optical follow-up observations
  2. GRB 241214A: GRBAlpha detection
  3. GRB 241213A (EP241213a): GRBAlpha detection
  4. GRB 241209D: GRBAlpha detection
  5. EP241217A: LCO optical observations
  6. EP241217a: Gemini-North detection of the likely optical counterpart
  7. EP241107a: VLA Radio Observation
  8. GRB 241213A: Swift-BAT refined analysis
  9. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  10. Konus-Wind detection of GRB 241213A (EP 241213a)
  11. GRB 241215A: Mondy AZT-33IK optical observations
  12. GRB 241215A: Nanshan/HMT optical upper limit
  13. GRB 241215A: Montarrenti Observatory optical upper limit
  14. GRB 241215A: GROWTH-India telescope optical upper limit
  15. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  16. GRB 241209B: SVOM/VT optical continuous fading
  17. GRB 241213A: SVOM/VT optical candidate
  18. GRB 241213B: Tiled Swift observations
  19. GRB 241213A: Swift/UVOT Upper Limits
  20. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  21. GRB 241212A: Fermi GBM detection
  22. EP241208a: NOT optical upper limits
  23. GRB 241212A: Swift ToO observations
  24. GRB 241213A: LCOGT Optical Upper Limits
  25. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  26. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  27. GRB 241213A: REM optical/NIR upper limits
  28. GRB241212A: OHP/T193 optical observations
  29. GRB 241213A: SAO RAS optical upper limit
  30. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  31. Swift GRB 241213A: Global MASTER-Net observations report
  32. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  33. GRB 241212A : SVOM/VT bright optical afterglow
  34. GRB 241212A: AstroSat CZTI detection
  35. GRB 241209B: GRANDMA/TRT upper limit
  36. GRB 241207A: TSHAO Zeiss-1000 optical observations
  37. GRB 241212A: SVOM detection of a bright long burst
  38. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  39. GRB 241209A: Chandra X-ray Detection
  40. Konus-Wind detection of GRB 241209B
  41. GRB 241207A: EIRSAT-1 GMOD Detection
  42. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  43. GRB 241209B: GRBAlpha detection
  44. GRB 241206C: GRBAlpha detection
  45. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  46. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  47. GRB 241129A: Fermi GBM Observation
  48. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  49. GRB 241209D: REM optical/NIR upper limits
  50. Konus-Wind detection of GRB 241209D
  51. GRB 241209B: Swift-XRT afterglow detection
  52. GRB 241209C: Fermi GBM Observation
  53. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  54. EP241208a: Optical upper limit with Kinder observations
  55. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  56. GRB 241209D: AstroSat CZTI detection
  57. GRB 241209A: EP-FXT follow-up observations
  58. GRB 241209B: SVOM/VT afterglow detection
  59. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  60. EP241208a: Global MASTER-Net observations report
  61. EP241208a: EP-FXT follow-up observations
  62. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  63. GRB 241207B: Fermi GBM Observation
  64. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  65. GRB 241209D: Fermi GBM Observation
  66. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  67. GRB 241209D: COLIBRÍ detection of the afterglow
  68. GRB 241209A: COLIBRÍ Optical Upper Limit
  69. Fermi GRB 241209D: Global MASTER-Net observations report
  70. GRB 241209A: Fermi GBM Observation
  71. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  72. GRB 241209A: GRANDMA/TAROT upper limit
  73. GRB 241209B: BOOTES-5 optical upper limit
  74. Swift GRB 241209D: Global MASTER-Net observations report
  75. Fermi GRB 241209C: Global MASTER-Net observations report
  76. Fermi GRB 241209E: Global MASTER-Net observations report
  77. GRB 241209B: Swift ToO observations
  78. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  79. GRB 241209A: REM optical/NIR observations
  80. GRB 241209C: AstroSat CZTI detection
  81. GRB 241209A: VLT/X-shooter spectroscopy
  82. GRB 241114B: cubesat Avion detection
  83. GRB 241209A: VLT optical observations
  84. Fermi GRB 241209A: Global MASTER-Net observations report
  85. GRB 241209A: GOTO optical upper limits
  86. Fermi GRB 241207B: Global MASTER-Net observations report
  87. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  88. GRB 241201A: AstroSat CZTI detection
  89. GRB 241206A: DDOTI Upper Limit on the Afterglow
  90. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  91. GRB 241207C: MASTER optical observations
  92. GRB 241207C: Tiled Swift observations
  93. Fermi GRB 241207A: Global MASTER-Net observations report
  94. EP241206a: Global MASTER-Net observations report
  95. GRB 241206A: Fermi GBM observation
  96. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  97. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  98. GRB 241206B: GWAC-F50A optical upper limit
  99. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  100. Fermi GRB 241206A: Global MASTER-Net observations report

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