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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"

3384 results found.

  1. EP251118a: Mondy, CrAO, Assy and SAO RAS/Zeiss-1000 optical observations
  2. EP251130a: Optical detections with Kinder observations
  3. EP251130a: GTC OSIRIS+ redshift z = 4.035 and rebrightening
  4. EP251130A: Optical observation from 1.3m DFOT
  5. EP251130a: refined analysis of the EP-WXT and EP-FXT observations
  6. EP251130a: Swift-XRT counterpart detection
  7. EP251130a: Global MASTER-Net observations report
  8. EP251130a: COLIBRÍ optical counterpart candidate
  9. EP251130a: Einstein Probe detection of an X-ray transient
  10. EP251129a/GRB 251129A: EP-FXT follow-up observations
  11. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  12. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  13. GRB 251129A: Swift-XRT afterglow detection
  14. The EP-WXT trigger 01709248941 is triggered by the known source Perseus Cluster
  15. GRB 251129A / EP251129a: SVOM/VT optical fading
  16. EP251129a: Global MASTER-Net observations report
  17. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  18. EP251124a: Pan-STARRS ri-band imaging and photometry
  19. EP251124b follow-up observation by EP-FXT
  20. EP251124b: NOT r- and z-band optical upper limits
  21. EP251124b: Global MASTER-Net observations report
  22. EP251124b: EP-WXT detection of a fast X-ray transient
  23. EP251124a: Xinglong GWAC-F60A optical observation
  24. EP251124a (EP-WXT trigger 01709248862) is triggered by the known source AWM 7
  25. EP251124a: NOT r- and z-band optical upper limits
  26. EP251124a: Global MASTER-Net observations report
  27. EP251124a: Swift-XRT observations
  28. EP251124a: Optical upper limit with Kinder observations
  29. EP251118A: 6 GHz VLA Detection
  30. LIGO/Virgo/KAGRA S251105aj: SVOM/VT optical observations and preliminary results on SVOM J2320.0-2901
  31. LIGO/Virgo/KAGRA S251105aj: EP-FXT follow-up observations and preliminary results on SVOM J2320.0-2901
  32. EP251124a: GROWTH-India Telescope optical upper limits
  33. EP251124a: Einstein Probe detection of an X-ray transient
  34. GRB 251122A/EP251122a: FTW optical and NIR observations
  35. GRB 251122A/EP251122A: 1.3m DFOT optical detection
  36. The EP-WXT trigger 01709248783 is likely a flaring star
  37. GRB 251122A / EP251122a: Xinglong 2.16m optical observation
  38. GRB 251122A / EP251122a: EP-FXT counterpart detection
  39. EP251122a: refined analysis of the EP-WXT and EP-FXT observations
  40. GRB 251122A/EP251122a: SVOM/VT optical observations with VHF data
  41. GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
  42. GRB 251122A / EP251122a: LCO optical upper limits
  43. EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
  44. EP251122a: Global MASTER-Net observations report
  45. GRB 251122A/EP251122a: SVOM/C-GFT upper limit
  46. GRB 251122A / EP251122a: SVOM detection of a long burst
  47. EP251122a: Einstein Probe detection of an X-ray transient
  48. EP251118a: Continued Optical Detection with Kinder observations
  49. LIGO/Virgo/KAGRA S251105aj: SVOM/ECLAIRs detection of a high-energy transient SVOM J2320.0-2901 through targeted search
  50. EP251118a: Xinglong-2.16m optical observation
  51. The EP-WXT trigger 01709248635 is likely a flaring star
  52. EP251118a: Optical detection with Kinder observations
  53. EP-WXT trigger 01709248403: confirmation of a stellar flare by SVOM/VT
  54. EP251118a / GRB 251118C: SVOM/VT optical observation
  55. The EP-WXT trigger 01709248403 is likely a flaring star
  56. EP251118a / GRB 251118C: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at CTIO
  57. GRB 251118C: Swift/BAT rates detection of a burst with a possible association with EP 251118A
  58. Konus-Wind detection of GRB 251118C (EP251118a)
  59. The EP-WXT trigger 01709248388 is likely a flaring star
  60. EP251118a: VLT near-infrared observation
  61. EP251118a: GOTO optical afterglow detection
  62. EP251118a: Global MASTER-Net observations report
  63. EP251118a: preliminary result of EP-FXT follow-up observation
  64. EP251118a: NOT candidate optical counterpart
  65. EP251118a: Einstein Probe detected of a fast X-ray transient
  66. GRB 251116B: SVOM/VT optical upper limit
  67. EP251023a: Assy AZT-20 optical observations
  68. EP251023a: UAFO and AbAO optical observations
  69. LIGO/Virgo/KAGRA S251112cm: EP-FXT follow-up observations
  70. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  71. GRB 251116B: EP-FXT follow-up observation
  72. Konus-Wind detection of GRB 251108C
  73. Konus-Wind detection of GRB 251103A
  74. The EP-WXT trigger 01709248221 is likely a flaring star
  75. GRB 251111A: SVOM/VT optical observations with X-band data
  76. GRB 251111A: Swift-XRT observations
  77. GRB 251111A: EP-FXT counterpart detection
  78. GRB 251013C: Chandra X-ray observations and jet break detection
  79. The EP-WXT trigger 01709248051 is likely a flaring star
  80. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  81. EP251102a: update of EP-FXT follow-up observation
  82. EP251102a: NIR observations with WINTER
  83. EP251102a: Einstein Probe detection of a fast X-ray transient
  84. EP251102a (WXT 11900459650): LCO observations confirm COLIBRÍ candidate
  85. EP251102.890: COLIBRÍ optical counterpart candidate
  86. Konus-Wind detection of GRB 251028A
  87. GRB 251026A/EP251026a: SVOM/VT optical counterpart
  88. GRB 251026A/EP251026a: EP-FXT follow-up observation
  89. The EP-WXT trigger 01709247588 is likely a flaring star
  90. The EP-WXT trigger 01709247525 is not a real source
  91. GRB 251023B: Swift-UVOT Upper Limits
  92. Konus-Wind detection of GRB 251022A
  93. EP251027.145: COLIBRÍ optical upper limits
  94. GRB 251026A/EP251026a: Einstein Probe detection of a fast X-ray transient
  95. Konus-Wind detection of GRB 251016A (short/hard)
  96. EP251023a: Mondy optical observations
  97. Konus-Wind detection of GRB 251016B
  98. EP251023a: MAO/AZT-22 optical observations
  99. EP251023b: Global MASTER-Net observations report
  100. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient

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