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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"

45805 results found.

  1. EP 241217a: NIR detection with P200/WIRC
  2. EP 241217a: Possible J-band detection with WINTER
  3. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  4. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  5. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  6. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  7. GRB 241217A / EP241217b: NOT optical upper limits
  8. GRB 241218A: REM optical upper limit
  9. GRB 241217A/EP241217b: REM optical/NIR upper limits
  10. EP241217a: REM optical/NIR upper limits
  11. GRB 241217a: Liverpool Telescope optical follow-up
  12. EP241217a: Liverpool Telescope optical follow-up
  13. GRB 241218A: Swift-XRT refined Analysis
  14. EP241217a: NOT optical observations
  15. EP241217a: GROWTH-India Telescope optical observations
  16. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  17. EP241119a: 7DT Optical upper limits
  18. EP241217b: Global MASTER-Net observations report
  19. GRB 241209A: ATCA radio follow-up observations
  20. EP241217a: Xinglong optical follow-up observations
  21. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  22. GRB 241218A: LCOGT Optical Upper Limit
  23. GRB 241218A: Enhanced Swift-XRT position
  24. EP241217a: Global MASTER-Net observations report
  25. GRB 241217A: GMG Optical Upper Limit
  26. GRB 241218A: Swift detection of a burst
  27. GRB 241217A : SVOM/VT optical afterglow detection
  28. GRB 241217A: Swift-XRT afterglow detection
  29. GRB 241217A: LCO optical upper limit
  30. GRB 241217A: GRANDMA/TAROT optical upperlimits
  31. EP241217a: Swift-XRT Detection
  32. EP241217A: Non-detection from Fermi-GBM Observations
  33. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  34. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  35. EP241217a: Kinder optical follow-up observations
  36. GRB 241214A: GRBAlpha detection
  37. GRB 241213A (EP241213a): GRBAlpha detection
  38. GRB 241209D: GRBAlpha detection
  39. EP241217A: LCO optical observations
  40. EP241217a: Gemini-North detection of the likely optical counterpart
  41. EP241217a: EP detection of an X-ray transient
  42. The EP-WXT trigger 01709129023 is likely a flaring star
  43. EP241107a: VLA Radio Observation
  44. GRB 241213A: Swift-BAT refined analysis
  45. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  46. Konus-Wind detection of GRB 241213A (EP 241213a)
  47. GRB 241215A: Mondy AZT-33IK optical observations
  48. GRB 241212A: Swift-XRT observations
  49. GRB 241214A: SVOM/GRM observation
  50. The EP-WXT trigger 01709128948 is likely a flaring star
  51. GRB 241215A: Nanshan/HMT optical upper limit
  52. GRB 241215A: Montarrenti Observatory optical upper limit
  53. GRB 241215A: GROWTH-India telescope optical upper limit
  54. GRB 241215A: A long GRB detected by INTEGRAL
  55. Integral GRB241215.58: Global MASTER-Net observations report
  56. The EP-WXT trigger 01709128921 is likely a flaring star
  57. GRB 241213B: Swift-XRT observations
  58. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  59. GRB 241209B: SVOM/VT optical continuous fading
  60. EP trigger ID 01709128824 is not a real source
  61. GRB 241213A: SVOM/VT optical candidate
  62. GRB 241213B: Tiled Swift observations
  63. GRB 241213A: Swift/UVOT Upper Limits
  64. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  65. GRB 241213A: Swift-XRT refined Analysis
  66. GRB 241212A: Fermi GBM detection
  67. EP241208a: NOT optical upper limits
  68. GRB 241212A: Swift ToO observations
  69. GRB 241213A: LCOGT Optical Upper Limits
  70. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  71. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  72. GRB 241213B: MAXI/GSC detection
  73. EP241213a: EP detection of An X-ray Transient
  74. GRB 241213A: REM optical/NIR upper limits
  75. GRB 241213A: Enhanced Swift-XRT position
  76. GRB241212A: OHP/T193 optical observations
  77. GRB 241213A: SAO RAS optical upper limit
  78. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  79. Swift GRB 241213A: Global MASTER-Net observations report
  80. GRB 241213A: Swift detection of a burst
  81. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  82. GRB 241212A : SVOM/VT bright optical afterglow
  83. GRB 241212A: AstroSat CZTI detection
  84. GRB 241209B: GRANDMA/TRT upper limit
  85. GRB 241207A: TSHAO Zeiss-1000 optical observations
  86. GRB 241212A: SVOM detection of a bright long burst
  87. GRB 241212A: Fermi GBM Final Real-time Localization
  88. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  89. GRB 241209A: Chandra X-ray Detection
  90. Konus-Wind detection of GRB 241209B
  91. GRB 241207A: EIRSAT-1 GMOD Detection
  92. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  93. GRB 241209B: GRBAlpha detection
  94. GRB 241206C: GRBAlpha detection
  95. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  96. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  97. GRB 241211A: Fermi GBM Final Real-time Localization
  98. GRB 241129A: Fermi GBM Observation
  99. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  100. GRB 241209D: REM optical/NIR upper limits

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