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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"

32724 results found.

  1. GRB 241218A: LCOGT Optical Upper Limit
  2. EP241217a: Global MASTER-Net observations report
  3. GRB 241217A: GMG Optical Upper Limit
  4. GRB 241217A : SVOM/VT optical afterglow detection
  5. GRB 241217A: LCO optical upper limit
  6. GRB 241217A: GRANDMA/TAROT optical upperlimits
  7. EP241217a: Swift-XRT Detection
  8. EP241217A: Non-detection from Fermi-GBM Observations
  9. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  10. EP241217a: Kinder optical follow-up observations
  11. GRB 241214A: GRBAlpha detection
  12. GRB 241213A (EP241213a): GRBAlpha detection
  13. GRB 241209D: GRBAlpha detection
  14. EP241217A: LCO optical observations
  15. EP241217a: Gemini-North detection of the likely optical counterpart
  16. EP241107a: VLA Radio Observation
  17. GRB 241213A: Swift-BAT refined analysis
  18. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  19. Konus-Wind detection of GRB 241213A (EP 241213a)
  20. GRB 241215A: Mondy AZT-33IK optical observations
  21. GRB 241215A: Nanshan/HMT optical upper limit
  22. GRB 241215A: Montarrenti Observatory optical upper limit
  23. GRB 241215A: GROWTH-India telescope optical upper limit
  24. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  25. GRB 241209B: SVOM/VT optical continuous fading
  26. GRB 241213A: SVOM/VT optical candidate
  27. GRB 241213B: Tiled Swift observations
  28. GRB 241213A: Swift/UVOT Upper Limits
  29. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  30. GRB 241212A: Fermi GBM detection
  31. EP241208a: NOT optical upper limits
  32. GRB 241212A: Swift ToO observations
  33. GRB 241213A: LCOGT Optical Upper Limits
  34. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  35. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  36. GRB 241213A: REM optical/NIR upper limits
  37. GRB241212A: OHP/T193 optical observations
  38. GRB 241213A: SAO RAS optical upper limit
  39. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  40. Swift GRB 241213A: Global MASTER-Net observations report
  41. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  42. GRB 241212A : SVOM/VT bright optical afterglow
  43. GRB 241212A: AstroSat CZTI detection
  44. GRB 241209B: GRANDMA/TRT upper limit
  45. GRB 241207A: TSHAO Zeiss-1000 optical observations
  46. GRB 241212A: SVOM detection of a bright long burst
  47. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  48. GRB 241209A: Chandra X-ray Detection
  49. Konus-Wind detection of GRB 241209B
  50. GRB 241207A: EIRSAT-1 GMOD Detection
  51. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  52. GRB 241209B: GRBAlpha detection
  53. GRB 241206C: GRBAlpha detection
  54. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  55. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  56. GRB 241129A: Fermi GBM Observation
  57. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  58. GRB 241209D: REM optical/NIR upper limits
  59. Konus-Wind detection of GRB 241209D
  60. GRB 241209B: Swift-XRT afterglow detection
  61. GRB 241209C: Fermi GBM Observation
  62. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  63. EP241208a: Optical upper limit with Kinder observations
  64. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  65. GRB 241209D: AstroSat CZTI detection
  66. GRB 241209A: EP-FXT follow-up observations
  67. GRB 241209B: SVOM/VT afterglow detection
  68. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  69. EP241208a: Global MASTER-Net observations report
  70. EP241208a: EP-FXT follow-up observations
  71. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  72. GRB 241207B: Fermi GBM Observation
  73. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  74. GRB 241209D: Fermi GBM Observation
  75. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  76. GRB 241209D: COLIBRÍ detection of the afterglow
  77. GRB 241209A: COLIBRÍ Optical Upper Limit
  78. Fermi GRB 241209D: Global MASTER-Net observations report
  79. GRB 241209A: Fermi GBM Observation
  80. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  81. GRB 241209A: GRANDMA/TAROT upper limit
  82. GRB 241209B: BOOTES-5 optical upper limit
  83. Swift GRB 241209D: Global MASTER-Net observations report
  84. Fermi GRB 241209C: Global MASTER-Net observations report
  85. Fermi GRB 241209E: Global MASTER-Net observations report
  86. GRB 241209B: Swift ToO observations
  87. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  88. GRB 241209A: REM optical/NIR observations
  89. GRB 241209C: AstroSat CZTI detection
  90. GRB 241209A: VLT/X-shooter spectroscopy
  91. GRB 241114B: cubesat Avion detection
  92. GRB 241209A: VLT optical observations
  93. Fermi GRB 241209A: Global MASTER-Net observations report
  94. GRB 241209A: GOTO optical upper limits
  95. Fermi GRB 241207B: Global MASTER-Net observations report
  96. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  97. GRB 241201A: AstroSat CZTI detection
  98. GRB 241206A: DDOTI Upper Limit on the Afterglow
  99. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  100. GRB 241207C: MASTER optical observations

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