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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"

32556 results found.

  1. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  2. EP260514a: NOT optical counterpart confirmation
  3. EP260514a: TRT optical counterpart candidate
  4. EP260514a: SVOM/VT optical candidate
  5. Fermi GRB 260516B: Global MASTER-Net observations report
  6. GRB 260515A: SVOM/VT optical observations
  7. GRB 260515A: OHP/T193 optical observations
  8. EP260514a: COLIBRÍ optical upper limits
  9. GRID detection of GRB 260507A
  10. GRB 260515A: GTC/OSIRIS+ spectroscopic redshift z = 0.764
  11. GRB 260515A: LCO optical observations
  12. SVOM GRB 260515A: Global MASTER-Net observations report
  13. GRB 260515A: NOT optical observations.
  14. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  15. GRB 260515A: SVOM/VT optical candidate from VHF data
  16. GRB 260515A: JinShan optical counterpart candidate
  17. GRB 260510C: Glowbug gamma-ray detection
  18. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  19. EP260514a: GROWTH-India Telescope optical upper limit
  20. GRB 260511B: NOT optical observations
  21. Konus-Wind detection of GRB 260512A
  22. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  23. GRB 260511B: GMG Optical Upper Limit
  24. EP260514a: Global MASTER-Net observations report
  25. EP260512a: LCO optical upper limits
  26. IPN triangulation of GRB 260512A
  27. GRB 260511B: Mephisto multi-band optical followup
  28. Fermi GRB 260514A: Global MASTER-Net observations report
  29. GRB 260512A: AstroSat CZTI detection
  30. EP260512a: EP-FXT follow-up observation
  31. EP260507a: Xinglong Schmidt optical counterpart detection
  32. EP260512a: Global MASTER-Net observations report
  33. Fermi GRB 260513A: Global MASTER-Net observations report
  34. Fermi GRB 260512A: Global MASTER-Net observations report
  35. GRB 260511B: further SAO RAS optical observations
  36. GRB 260509A: SVOM/VT optical observations
  37. Konus-Wind detection of GRB 260511B
  38. EP260512a: COLIBRÍ optical upper limits
  39. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  40. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  41. GRB 260512A: NuSTAR detection of prompt emission
  42. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  43. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  44. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  45. GRB 260511A: Glowbug gamma-ray detection
  46. Konus-Wind detection of GRB 260511A
  47. MASS-Cube (GRID 2.0) detection of GRB 260511A
  48. MASS-Cube (GRID 2.0) detection of GRB 260507A
  49. GRB 260511B: SAO RAS optical observations
  50. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  51. GRB 260511B: FRAM-ORM optical detection
  52. GRB 260511A: EP-FXT follow-up observation
  53. GRB 260511B: EP-FXT follow-up observation
  54. GRB 260511B: LCO optical counterpart detection
  55. GRB260511B: MAO/AZT-22 optical observations
  56. GRB 260511A: SVOM/VT optical observations
  57. GRB 260511B: LCO optical observations
  58. GRB 260511B: OHP/T193 spectroscopic observations
  59. GRB 260511B: GOTO optical counterpart detection
  60. GRB 260511B: Xinglong 2.16m/BEFOSC redshift confirmation
  61. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  62. GRB 260511B: SVOM/VT optical observations
  63. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  64. GRB 260510B: EP-FXT follow-up observation
  65. GRB 260511B: OSIRIS+/GTC redshift z=2.006
  66. GRB 260510C: Fermi GBM Observation
  67. GRB 260509A: SAO RAS optical observations
  68. GRB 260511A: REM near-infrared detection
  69. GRB 260511B: GROWTH-India Telescope optical observations
  70. GRB 260511B: AstroSat CZTI detection
  71. GRB 260506B: Glowbug gamma-ray detection
  72. GRB 260506A: Glowbug gamma-ray detection of a short burst
  73. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  74. GRB 260511B: NuSTAR detection of prompt emission
  75. GRB 260511A: NuSTAR detection of prompt emission
  76. GRB 260511B: Fermi GBM Detection
  77. GRB 260511B: SVOM/VT optical observation with VHF data
  78. GRB 260511B: TRT optical observation
  79. GRB 260510B: SVOM/ECLAIRs refined analysis
  80. GRB 260511B : MITSuME Akeno optical afterglow candidate detection
  81. GRB 260511A: Fermi GBM Detection
  82. GRB 260511B SVOM/C-GFT optical counterpart detection
  83. EP260509a: LCO optical upper limits
  84. GRB 260511A: UTGO H50 optical afterglow observation
  85. GRB 260510C: AstroSat CZTI detection
  86. GRB 260511B: SVOM detection of a burst
  87. GRB 260510C: EP-FXT follow-up observation
  88. GRB 260510C: SVOM/VT optical counterpart confirmation
  89. EP260509a: EP-FXT non-detection and upper limit
  90. GRB 260511A: SVOM/VT optical observation with VHF data
  91. Fermi GRB 260511A: Global MASTER-Net observations report
  92. GRB 260511A: KAIT optical afterglow observations
  93. GRB 260511A: LCO optical afterglow detection
  94. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  95. GRB 260511A: TRT optical counterpart detection
  96. GRB 260511A: SVOM detection of a bright burst
  97. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  98. GRB 260510B: SVOM/VT optical upper limits
  99. GRB 260510C: SVOM/VT optical upper limits
  100. GRB 260510C: MAXI/GSC detection

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