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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"

3377 results found.

  1. EP251130a: COLIBRÍ optical counterpart candidate
  2. EP251130a: Einstein Probe detection of an X-ray transient
  3. EP251129a/GRB 251129A: EP-FXT follow-up observations
  4. GRB 251129A / EP251129a: GTC/OSIRIS+ spectroscopic redshift z = 1.460
  5. GRB 251129A / EP251129a: OSN and CAHA optical follow-up
  6. GRB 251129A: Swift-XRT afterglow detection
  7. The EP-WXT trigger 01709248941 is triggered by the known source Perseus Cluster
  8. GRB 251129A / EP251129a: SVOM/VT optical fading
  9. EP251129a: Global MASTER-Net observations report
  10. EP251129a/GRB 251129A : Einstein Probe detection of an X-ray transient
  11. EP251124a: Pan-STARRS ri-band imaging and photometry
  12. EP251124b follow-up observation by EP-FXT
  13. EP251124b: NOT r- and z-band optical upper limits
  14. EP251124b: Global MASTER-Net observations report
  15. EP251124b: EP-WXT detection of a fast X-ray transient
  16. EP251124a: Xinglong GWAC-F60A optical observation
  17. EP251124a (EP-WXT trigger 01709248862) is triggered by the known source AWM 7
  18. EP251124a: NOT r- and z-band optical upper limits
  19. EP251124a: Global MASTER-Net observations report
  20. EP251124a: Swift-XRT observations
  21. EP251124a: Optical upper limit with Kinder observations
  22. EP251118A: 6 GHz VLA Detection
  23. LIGO/Virgo/KAGRA S251105aj: SVOM/VT optical observations and preliminary results on SVOM J2320.0-2901
  24. LIGO/Virgo/KAGRA S251105aj: EP-FXT follow-up observations and preliminary results on SVOM J2320.0-2901
  25. EP251124a: GROWTH-India Telescope optical upper limits
  26. EP251124a: Einstein Probe detection of an X-ray transient
  27. GRB 251122A/EP251122a: FTW optical and NIR observations
  28. GRB 251122A/EP251122A: 1.3m DFOT optical detection
  29. The EP-WXT trigger 01709248783 is likely a flaring star
  30. GRB 251122A / EP251122a: Xinglong 2.16m optical observation
  31. GRB 251122A / EP251122a: EP-FXT counterpart detection
  32. EP251122a: refined analysis of the EP-WXT and EP-FXT observations
  33. GRB 251122A/EP251122a: SVOM/VT optical observations with VHF data
  34. GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
  35. GRB 251122A / EP251122a: LCO optical upper limits
  36. EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
  37. EP251122a: Global MASTER-Net observations report
  38. GRB 251122A/EP251122a: SVOM/C-GFT upper limit
  39. GRB 251122A / EP251122a: SVOM detection of a long burst
  40. EP251122a: Einstein Probe detection of an X-ray transient
  41. EP251118a: Continued Optical Detection with Kinder observations
  42. LIGO/Virgo/KAGRA S251105aj: SVOM/ECLAIRs detection of a high-energy transient SVOM J2320.0-2901 through targeted search
  43. EP251118a: Xinglong-2.16m optical observation
  44. The EP-WXT trigger 01709248635 is likely a flaring star
  45. EP251118a: Optical detection with Kinder observations
  46. EP-WXT trigger 01709248403: confirmation of a stellar flare by SVOM/VT
  47. EP251118a / GRB 251118C: SVOM/VT optical observation
  48. The EP-WXT trigger 01709248403 is likely a flaring star
  49. EP251118a / GRB 251118C: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 1-m telescope at CTIO
  50. GRB 251118C: Swift/BAT rates detection of a burst with a possible association with EP 251118A
  51. Konus-Wind detection of GRB 251118C (EP251118a)
  52. The EP-WXT trigger 01709248388 is likely a flaring star
  53. EP251118a: VLT near-infrared observation
  54. EP251118a: GOTO optical afterglow detection
  55. EP251118a: Global MASTER-Net observations report
  56. EP251118a: preliminary result of EP-FXT follow-up observation
  57. EP251118a: NOT candidate optical counterpart
  58. EP251118a: Einstein Probe detected of a fast X-ray transient
  59. GRB 251116B: SVOM/VT optical upper limit
  60. EP251023a: Assy AZT-20 optical observations
  61. EP251023a: UAFO and AbAO optical observations
  62. LIGO/Virgo/KAGRA S251112cm: EP-FXT follow-up observations
  63. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  64. GRB 251116B: EP-FXT follow-up observation
  65. Konus-Wind detection of GRB 251108C
  66. Konus-Wind detection of GRB 251103A
  67. The EP-WXT trigger 01709248221 is likely a flaring star
  68. GRB 251111A: SVOM/VT optical observations with X-band data
  69. GRB 251111A: Swift-XRT observations
  70. GRB 251111A: EP-FXT counterpart detection
  71. GRB 251013C: Chandra X-ray observations and jet break detection
  72. The EP-WXT trigger 01709248051 is likely a flaring star
  73. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  74. EP251102a: update of EP-FXT follow-up observation
  75. EP251102a: NIR observations with WINTER
  76. EP251102a: Einstein Probe detection of a fast X-ray transient
  77. EP251102a (WXT 11900459650): LCO observations confirm COLIBRÍ candidate
  78. EP251102.890: COLIBRÍ optical counterpart candidate
  79. Konus-Wind detection of GRB 251028A
  80. GRB 251026A/EP251026a: SVOM/VT optical counterpart
  81. GRB 251026A/EP251026a: EP-FXT follow-up observation
  82. The EP-WXT trigger 01709247588 is likely a flaring star
  83. The EP-WXT trigger 01709247525 is not a real source
  84. GRB 251023B: Swift-UVOT Upper Limits
  85. Konus-Wind detection of GRB 251022A
  86. EP251027.145: COLIBRÍ optical upper limits
  87. GRB 251026A/EP251026a: Einstein Probe detection of a fast X-ray transient
  88. Konus-Wind detection of GRB 251016A (short/hard)
  89. EP251023a: Mondy optical observations
  90. Konus-Wind detection of GRB 251016B
  91. EP251023a: MAO/AZT-22 optical observations
  92. EP251023b: Global MASTER-Net observations report
  93. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  94. EP251023a: GROWTH-India Telescope optical observations
  95. GRB 251023B: Glowbug gamma-ray detection
  96. EP251023a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at Teide Observatory
  97. EP251023a: Global MASTER-Net observations report
  98. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  99. EP#01709247298: Swift-XRT counterpart detection
  100. EP251023a: Keck/LRIS spectroscopic redshift z=2.232

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