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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

31728 results found.

  1. GRB 241209A: ATCA radio follow-up observations
  2. EP241217a: Xinglong optical follow-up observations
  3. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  4. GRB 241218A: LCOGT Optical Upper Limit
  5. EP241217a: Global MASTER-Net observations report
  6. GRB 241217A: GMG Optical Upper Limit
  7. GRB 241217A : SVOM/VT optical afterglow detection
  8. GRB 241217A: LCO optical upper limit
  9. GRB 241217A: GRANDMA/TAROT optical upperlimits
  10. EP241217a: Swift-XRT Detection
  11. EP241217A: Non-detection from Fermi-GBM Observations
  12. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  13. EP241217a: Kinder optical follow-up observations
  14. GRB 241214A: GRBAlpha detection
  15. GRB 241213A (EP241213a): GRBAlpha detection
  16. GRB 241209D: GRBAlpha detection
  17. EP241217A: LCO optical observations
  18. EP241217a: Gemini-North detection of the likely optical counterpart
  19. EP241107a: VLA Radio Observation
  20. GRB 241213A: Swift-BAT refined analysis
  21. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  22. Konus-Wind detection of GRB 241213A (EP 241213a)
  23. GRB 241215A: Mondy AZT-33IK optical observations
  24. GRB 241215A: Nanshan/HMT optical upper limit
  25. GRB 241215A: Montarrenti Observatory optical upper limit
  26. GRB 241215A: GROWTH-India telescope optical upper limit
  27. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  28. GRB 241209B: SVOM/VT optical continuous fading
  29. GRB 241213A: SVOM/VT optical candidate
  30. GRB 241213B: Tiled Swift observations
  31. GRB 241213A: Swift/UVOT Upper Limits
  32. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  33. GRB 241212A: Fermi GBM detection
  34. EP241208a: NOT optical upper limits
  35. GRB 241212A: Swift ToO observations
  36. GRB 241213A: LCOGT Optical Upper Limits
  37. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  38. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  39. GRB 241213A: REM optical/NIR upper limits
  40. GRB241212A: OHP/T193 optical observations
  41. GRB 241213A: SAO RAS optical upper limit
  42. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  43. Swift GRB 241213A: Global MASTER-Net observations report
  44. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  45. GRB 241212A : SVOM/VT bright optical afterglow
  46. GRB 241212A: AstroSat CZTI detection
  47. GRB 241209B: GRANDMA/TRT upper limit
  48. GRB 241207A: TSHAO Zeiss-1000 optical observations
  49. GRB 241212A: SVOM detection of a bright long burst
  50. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  51. GRB 241209A: Chandra X-ray Detection
  52. Konus-Wind detection of GRB 241209B
  53. GRB 241207A: EIRSAT-1 GMOD Detection
  54. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  55. GRB 241209B: GRBAlpha detection
  56. GRB 241206C: GRBAlpha detection
  57. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  58. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  59. GRB 241129A: Fermi GBM Observation
  60. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  61. GRB 241209D: REM optical/NIR upper limits
  62. Konus-Wind detection of GRB 241209D
  63. GRB 241209B: Swift-XRT afterglow detection
  64. GRB 241209C: Fermi GBM Observation
  65. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  66. EP241208a: Optical upper limit with Kinder observations
  67. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  68. GRB 241209D: AstroSat CZTI detection
  69. GRB 241209A: EP-FXT follow-up observations
  70. GRB 241209B: SVOM/VT afterglow detection
  71. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  72. EP241208a: Global MASTER-Net observations report
  73. EP241208a: EP-FXT follow-up observations
  74. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  75. GRB 241207B: Fermi GBM Observation
  76. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  77. GRB 241209D: Fermi GBM Observation
  78. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  79. GRB 241209D: COLIBRÍ detection of the afterglow
  80. GRB 241209A: COLIBRÍ Optical Upper Limit
  81. Fermi GRB 241209D: Global MASTER-Net observations report
  82. GRB 241209A: Fermi GBM Observation
  83. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  84. GRB 241209A: GRANDMA/TAROT upper limit
  85. GRB 241209B: BOOTES-5 optical upper limit
  86. Swift GRB 241209D: Global MASTER-Net observations report
  87. Fermi GRB 241209C: Global MASTER-Net observations report
  88. Fermi GRB 241209E: Global MASTER-Net observations report
  89. GRB 241209B: Swift ToO observations
  90. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  91. GRB 241209A: REM optical/NIR observations
  92. GRB 241209C: AstroSat CZTI detection
  93. GRB 241209A: VLT/X-shooter spectroscopy
  94. GRB 241114B: cubesat Avion detection
  95. GRB 241209A: VLT optical observations
  96. Fermi GRB 241209A: Global MASTER-Net observations report
  97. GRB 241209A: GOTO optical upper limits
  98. Fermi GRB 241207B: Global MASTER-Net observations report
  99. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  100. GRB 241201A: AstroSat CZTI detection

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