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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"

32705 results found.

  1. GRB 241215A: Mondy AZT-33IK optical observations
  2. GRB 241215A: Nanshan/HMT optical upper limit
  3. GRB 241215A: Montarrenti Observatory optical upper limit
  4. GRB 241215A: GROWTH-India telescope optical upper limit
  5. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  6. GRB 241209B: SVOM/VT optical continuous fading
  7. GRB 241213A: SVOM/VT optical candidate
  8. GRB 241213B: Tiled Swift observations
  9. GRB 241213A: Swift/UVOT Upper Limits
  10. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  11. GRB 241212A: Fermi GBM detection
  12. EP241208a: NOT optical upper limits
  13. GRB 241212A: Swift ToO observations
  14. GRB 241213A: LCOGT Optical Upper Limits
  15. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  16. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  17. GRB 241213A: REM optical/NIR upper limits
  18. GRB241212A: OHP/T193 optical observations
  19. GRB 241213A: SAO RAS optical upper limit
  20. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  21. Swift GRB 241213A: Global MASTER-Net observations report
  22. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  23. GRB 241212A : SVOM/VT bright optical afterglow
  24. GRB 241212A: AstroSat CZTI detection
  25. GRB 241209B: GRANDMA/TRT upper limit
  26. GRB 241207A: TSHAO Zeiss-1000 optical observations
  27. GRB 241212A: SVOM detection of a bright long burst
  28. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  29. GRB 241209A: Chandra X-ray Detection
  30. Konus-Wind detection of GRB 241209B
  31. GRB 241207A: EIRSAT-1 GMOD Detection
  32. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  33. GRB 241209B: GRBAlpha detection
  34. GRB 241206C: GRBAlpha detection
  35. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  36. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  37. GRB 241129A: Fermi GBM Observation
  38. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  39. GRB 241209D: REM optical/NIR upper limits
  40. Konus-Wind detection of GRB 241209D
  41. GRB 241209B: Swift-XRT afterglow detection
  42. GRB 241209C: Fermi GBM Observation
  43. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  44. EP241208a: Optical upper limit with Kinder observations
  45. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  46. GRB 241209D: AstroSat CZTI detection
  47. GRB 241209A: EP-FXT follow-up observations
  48. GRB 241209B: SVOM/VT afterglow detection
  49. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  50. EP241208a: Global MASTER-Net observations report
  51. EP241208a: EP-FXT follow-up observations
  52. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  53. GRB 241207B: Fermi GBM Observation
  54. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  55. GRB 241209D: Fermi GBM Observation
  56. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  57. GRB 241209D: COLIBRÍ detection of the afterglow
  58. GRB 241209A: COLIBRÍ Optical Upper Limit
  59. Fermi GRB 241209D: Global MASTER-Net observations report
  60. GRB 241209A: Fermi GBM Observation
  61. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  62. GRB 241209A: GRANDMA/TAROT upper limit
  63. GRB 241209B: BOOTES-5 optical upper limit
  64. Swift GRB 241209D: Global MASTER-Net observations report
  65. Fermi GRB 241209C: Global MASTER-Net observations report
  66. Fermi GRB 241209E: Global MASTER-Net observations report
  67. GRB 241209B: Swift ToO observations
  68. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  69. GRB 241209A: REM optical/NIR observations
  70. GRB 241209C: AstroSat CZTI detection
  71. GRB 241209A: VLT/X-shooter spectroscopy
  72. GRB 241114B: cubesat Avion detection
  73. GRB 241209A: VLT optical observations
  74. Fermi GRB 241209A: Global MASTER-Net observations report
  75. GRB 241209A: GOTO optical upper limits
  76. Fermi GRB 241207B: Global MASTER-Net observations report
  77. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  78. GRB 241201A: AstroSat CZTI detection
  79. GRB 241206A: DDOTI Upper Limit on the Afterglow
  80. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  81. GRB 241207C: MASTER optical observations
  82. GRB 241207C: Tiled Swift observations
  83. Fermi GRB 241207A: Global MASTER-Net observations report
  84. EP241206a: Global MASTER-Net observations report
  85. GRB 241206A: Fermi GBM observation
  86. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  87. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  88. GRB 241206B: GWAC-F50A optical upper limit
  89. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  90. Fermi GRB 241206A: Global MASTER-Net observations report
  91. EP241201a: 1.6m Mephisto Optical Upper Limits
  92. GRB 241204A: COLIBRÍ Optical Upper Limit
  93. EP241202b: KAIT optical upper limit
  94. GRB 241204A: DDOTI Upper Limits on the Afterglow
  95. GRB 241204A: Fermi GBM Observation
  96. Fermi GRB 241204A: Global MASTER-Net observations report
  97. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  98. GRB 241128A : RAPAS follow-up observations
  99. GRB 241201A: GRBAlpha detection
  100. EP241202b: Upper limits from Fermi-GBM Observations

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