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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"
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submitter:"Judith Racusin"

18538 results found.

  1. EP241103a: an X-ray transient detected by Einstein Probe
  2. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  3. GRB241030A: OHP/T193 optical observations
  4. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  5. EP241101a: EP-WXT detection of a fast X-ray transient
  6. GRB 241101A: FRAM-ORM optical limit
  7. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  8. GRB 241101A: Swift-BAT refined analysis
  9. GRB 241030A: further SAO RAS optical observations
  10. GRB 241030A: Optical Observations via Virtual Telescope Project
  11. EP241021a: Liverpool Telescope optical follow-up observations
  12. GRB 241026A: SAO RAS optical observations
  13. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  14. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  15. EP241021a: OHP/T193 optical observations
  16. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  17. GRB 241030B: Montarrenti Observatory optical upper limit
  18. EP241026b: Liverpool Telescope optical follow-up
  19. GRB 241030A: SAO RAS optical observations
  20. EP241021a: AMI-LA radio detection
  21. GRB 241030B : GIT optical upper limits
  22. GRB 241030B: LCOGT Optical Upper Limits
  23. GRB 241030B: Swift-BAT refined analysis
  24. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  25. GRB 241030B: Swift/UVOT Detection
  26. GRB 241029A: LCO optical detection
  27. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  28. GRB 241030B : MITSuME Akeno optical upper limits
  29. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  30. GRB 241030B: SVOM/VT optical afterglow observations
  31. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  32. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  33. GRB 241030B: BTA observations
  34. GRB 241029A: SVOM/VT optical afterglow observations
  35. GRB 241030B: Enhanced Swift-XRT position
  36. GRB241030B: GRANDMA/TAROT Upper Limit
  37. GRB 241030A: Swift-XRT refined Analysis
  38. GRB 241030B: SAO RAS optical observations
  39. GRB 241030B: AKO Optical Afterglow Detection
  40. GRB 241030B: Nanshan/HMT optical afterglow detection
  41. GRB 241030B: Swift detection of a burst
  42. GRB 240912A: radio detection with the VLA
  43. GRB 241030A: AKO Optical Afterglow Detection
  44. GRB 241030A: Swift/UVOT Detection
  45. GRB 241030A: SVOM/C-GFT optical observations
  46. GRB 241026A: LBT optical observations
  47. EP241021a: Optical rebrightening observations with Mephisto
  48. EP241026b: EP-FXT follow-up observation
  49. GRB 241030A: Multiband optical detection with Mephisto
  50. GRB 241030A: SVOM/VT optical afterglow observations
  51. GRB 241030A : MITSuME Akeno optical afterglow detection
  52. GRB 241030A: Enhanced Swift-XRT position
  53. GRB 241029A: GROWTH-India Telescope optical follow up
  54. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  55. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  56. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  57. GRB 241029A: SAO RAS optical observations
  58. GRB 241026A: SAO RAS optical observations
  59. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  60. EP241021a: SAO RAS observations of rebrightening
  61. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  62. EP241021a: ATCA radio observations
  63. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  64. GRB 241026A: Swift/UVOT Upper Limits
  65. GRB 241029A: AKO Optical Afterglow Detection
  66. EP241021a: continued SOAR observations confirm optical rebrightening
  67. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  68. GRB 241029A: Mephisto observations
  69. EP 241026b: LBT possible optical counterpart (brightening source)
  70. GRB 241029A: TRT optical afterglow candidate detection
  71. GRB 241026A: TNOT optical counterpart detection
  72. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  73. GRB 241025A: further SAO RAS optical observations
  74. GRB 241026A: BTA and Zeiss-1000 optical observations
  75. GRB 241026A: SVOM/GRM observation
  76. EP241026B: GROWTH-India Telescope optical upper limit
  77. GRB 241025A: Swift/UVOT Detection
  78. GRB 241026A: GROWTH-India Telescope optical observations
  79. GRB 241026A: J-band observations with WINTER
  80. GRB 241025A: SAO RAS optical observations
  81. GRB 241026A: Las Cumbres optical detection
  82. GRB 241025A: Mondy optical observations
  83. EP241021a: SOAR observations of the optical counterpart
  84. EP241021a: further SAO RAS optical observations
  85. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  86. GRB 241026A: Swift-XRT refined Analysis
  87. EP 241026b: LBT optical observations
  88. GRB 241026A: Enhanced Swift-XRT position
  89. EP241026b: EP detection of a fast X-ray transient
  90. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  91. GRB 241026A: SAO RAS observations of possible optical afterglow
  92. GRB 241026A: Swift detection of a burst
  93. GRB241025A: 1.3m DFOT optical afterglow detection
  94. EP241021a: optical follow-up observations with Xinglong Observatory
  95. GRB 241025A: GROWTH-India Telescope optical observations
  96. GRB 241025A: COLIBRÍ Detection of the Afterglow
  97. IPN triangulation of GRB 241022A (short/hard)
  98. EP241025a (GRB 241025A): EP observations update
  99. GRB 241025A : SVOM/VT optical afterglow observations
  100. EP241021a: Liverpool Telescope optical follow-up observations

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