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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"

32718 results found.

  1. EP241217A: Non-detection from Fermi-GBM Observations
  2. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  3. EP241217a: Kinder optical follow-up observations
  4. GRB 241214A: GRBAlpha detection
  5. GRB 241213A (EP241213a): GRBAlpha detection
  6. GRB 241209D: GRBAlpha detection
  7. EP241217A: LCO optical observations
  8. EP241217a: Gemini-North detection of the likely optical counterpart
  9. EP241107a: VLA Radio Observation
  10. GRB 241213A: Swift-BAT refined analysis
  11. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  12. Konus-Wind detection of GRB 241213A (EP 241213a)
  13. GRB 241215A: Mondy AZT-33IK optical observations
  14. GRB 241215A: Nanshan/HMT optical upper limit
  15. GRB 241215A: Montarrenti Observatory optical upper limit
  16. GRB 241215A: GROWTH-India telescope optical upper limit
  17. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  18. GRB 241209B: SVOM/VT optical continuous fading
  19. GRB 241213A: SVOM/VT optical candidate
  20. GRB 241213B: Tiled Swift observations
  21. GRB 241213A: Swift/UVOT Upper Limits
  22. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  23. GRB 241212A: Fermi GBM detection
  24. EP241208a: NOT optical upper limits
  25. GRB 241212A: Swift ToO observations
  26. GRB 241213A: LCOGT Optical Upper Limits
  27. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  28. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  29. GRB 241213A: REM optical/NIR upper limits
  30. GRB241212A: OHP/T193 optical observations
  31. GRB 241213A: SAO RAS optical upper limit
  32. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  33. Swift GRB 241213A: Global MASTER-Net observations report
  34. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  35. GRB 241212A : SVOM/VT bright optical afterglow
  36. GRB 241212A: AstroSat CZTI detection
  37. GRB 241209B: GRANDMA/TRT upper limit
  38. GRB 241207A: TSHAO Zeiss-1000 optical observations
  39. GRB 241212A: SVOM detection of a bright long burst
  40. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  41. GRB 241209A: Chandra X-ray Detection
  42. Konus-Wind detection of GRB 241209B
  43. GRB 241207A: EIRSAT-1 GMOD Detection
  44. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  45. GRB 241209B: GRBAlpha detection
  46. GRB 241206C: GRBAlpha detection
  47. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  48. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  49. GRB 241129A: Fermi GBM Observation
  50. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  51. GRB 241209D: REM optical/NIR upper limits
  52. Konus-Wind detection of GRB 241209D
  53. GRB 241209B: Swift-XRT afterglow detection
  54. GRB 241209C: Fermi GBM Observation
  55. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  56. EP241208a: Optical upper limit with Kinder observations
  57. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  58. GRB 241209D: AstroSat CZTI detection
  59. GRB 241209A: EP-FXT follow-up observations
  60. GRB 241209B: SVOM/VT afterglow detection
  61. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  62. EP241208a: Global MASTER-Net observations report
  63. EP241208a: EP-FXT follow-up observations
  64. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  65. GRB 241207B: Fermi GBM Observation
  66. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  67. GRB 241209D: Fermi GBM Observation
  68. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  69. GRB 241209D: COLIBRÍ detection of the afterglow
  70. GRB 241209A: COLIBRÍ Optical Upper Limit
  71. Fermi GRB 241209D: Global MASTER-Net observations report
  72. GRB 241209A: Fermi GBM Observation
  73. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  74. GRB 241209A: GRANDMA/TAROT upper limit
  75. GRB 241209B: BOOTES-5 optical upper limit
  76. Swift GRB 241209D: Global MASTER-Net observations report
  77. Fermi GRB 241209C: Global MASTER-Net observations report
  78. Fermi GRB 241209E: Global MASTER-Net observations report
  79. GRB 241209B: Swift ToO observations
  80. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  81. GRB 241209A: REM optical/NIR observations
  82. GRB 241209C: AstroSat CZTI detection
  83. GRB 241209A: VLT/X-shooter spectroscopy
  84. GRB 241114B: cubesat Avion detection
  85. GRB 241209A: VLT optical observations
  86. Fermi GRB 241209A: Global MASTER-Net observations report
  87. GRB 241209A: GOTO optical upper limits
  88. Fermi GRB 241207B: Global MASTER-Net observations report
  89. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  90. GRB 241201A: AstroSat CZTI detection
  91. GRB 241206A: DDOTI Upper Limit on the Afterglow
  92. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  93. GRB 241207C: MASTER optical observations
  94. GRB 241207C: Tiled Swift observations
  95. Fermi GRB 241207A: Global MASTER-Net observations report
  96. EP241206a: Global MASTER-Net observations report
  97. GRB 241206A: Fermi GBM observation
  98. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  99. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  100. GRB 241206B: GWAC-F50A optical upper limit

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