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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"

24466 results found.

  1. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  2. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  3. GRB 241218A: REM optical upper limit
  4. GRB 241217A/EP241217b: REM optical/NIR upper limits
  5. EP241217a: REM optical/NIR upper limits
  6. EP241217a: GROWTH-India Telescope optical observations
  7. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  8. EP241119a: 7DT Optical upper limits
  9. EP241217b: Global MASTER-Net observations report
  10. EP241217a: Xinglong optical follow-up observations
  11. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  12. GRB 241218A: LCOGT Optical Upper Limit
  13. EP241217a: Global MASTER-Net observations report
  14. EP241217A: Non-detection from Fermi-GBM Observations
  15. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  16. GRB 241214A: GRBAlpha detection
  17. GRB 241213A (EP241213a): GRBAlpha detection
  18. GRB 241209D: GRBAlpha detection
  19. EP241217a: EP detection of an X-ray transient
  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 241214A: SVOM/GRM observation
  25. GRB 241215A: GROWTH-India telescope optical upper limit
  26. GRB 241215A: A long GRB detected by INTEGRAL
  27. Integral GRB241215.58: Global MASTER-Net observations report
  28. GRB 241213B: Swift-XRT observations
  29. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  30. GRB 241209B: SVOM/VT optical continuous fading
  31. EP trigger ID 01709128824 is not a real source
  32. GRB 241213A: SVOM/VT optical candidate
  33. GRB 241212A: Fermi GBM detection
  34. GRB 241213A: LCOGT Optical Upper Limits
  35. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  36. EP241213a: EP detection of An X-ray Transient
  37. GRB 241213A: REM optical/NIR upper limits
  38. GRB241212A: OHP/T193 optical observations
  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 detection of a bright long burst
  43. GRB 241212A: Fermi GBM Final Real-time Localization
  44. GRB 241209A: Chandra X-ray Detection
  45. Konus-Wind detection of GRB 241209B
  46. GRB 241207A: EIRSAT-1 GMOD Detection
  47. GRB 241209B: GRBAlpha detection
  48. GRB 241206C: GRBAlpha detection
  49. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  50. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  51. GRB 241211A: Fermi GBM Final Real-time Localization
  52. GRB 241129A: Fermi GBM Observation
  53. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  54. GRB 241209D: REM optical/NIR upper limits
  55. Konus-Wind detection of GRB 241209D
  56. GRB 241209B: Swift-XRT afterglow detection
  57. GRB 241209C: Fermi GBM Observation
  58. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  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. Fermi trigger No 755485387: Global MASTER-Net observations report
  66. GRB 241207B: Fermi GBM Observation
  67. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  68. GRB 241209D: Fermi GBM Observation
  69. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  70. Fermi GRB 241209D: Global MASTER-Net observations report
  71. GRB 241209A: Fermi GBM Observation
  72. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  73. Swift GRB 241209D: Global MASTER-Net observations report
  74. Fermi GRB 241209C: Global MASTER-Net observations report
  75. Fermi GRB 241209E: Global MASTER-Net observations report
  76. GRB 241209E: Fermi GBM Final Real-time Localization
  77. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  78. GRB 241209A: REM optical/NIR observations
  79. GRB 241209D: Fermi GBM Final Real-time Localization
  80. GRB 241209A: VLT/X-shooter spectroscopy
  81. GRB 241114B: cubesat Avion detection
  82. GRB 241209A: VLT optical observations
  83. Fermi GRB 241209A: Global MASTER-Net observations report
  84. GRB 241209C: Fermi GBM Final Real-time Localization
  85. EP241206a: 1.5m OSN optical limit
  86. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  87. Swift GRB241209.23: Global MASTER-Net observations report
  88. GRB 241209A: Fermi GBM Final Real-time Localization
  89. Fermi GRB 241207B: Global MASTER-Net observations report
  90. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  91. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  92. EP241206a: BOOTES Global Network optical limits
  93. GRB 241207C: MASTER optical observations
  94. Fermi trigger No 755225799: Global MASTER-Net observations report
  95. GRB 241207B: Fermi GBM Final Real-time Localization
  96. Fermi trigger No 755277791: Global MASTER-Net observations report
  97. Fermi GRB 241207A: Global MASTER-Net observations report
  98. EP241206a: Global MASTER-Net observations report
  99. GRB 241206A: Fermi GBM observation
  100. GRB 241206C: SVOM/GRM observation of a likely short burst

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