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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"

23614 results found.

  1. GRB 241006A: PRIME near-infrared upper limits
  2. GRB 241006A: Swift/UVOT Upper Limits
  3. GRB 241006A: SVOM/VT follow-up and optical upper limit
  4. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  5. GRB 241001A: Swift-XRT afterglow detection
  6. GRB 241006A: Enhanced Swift-XRT position
  7. GRB 241006A: Swift detection of a burst
  8. GRB 240930B: SVOM/C-GFT optical upper limit
  9. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  10. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  11. GRB 241002B: Swift-XRT observations
  12. GRB 241002C: SVOM/C-GFT optical upper limit
  13. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  14. Konus-Wind detection of GRB 240926A
  15. GRB 241002B: PRIME near-infrared detection
  16. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  17. IPN triangulation of GRB 240930B / EP 240930a
  18. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  19. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  20. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  21. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  22. GRB 241002C : MITSuME Akeno optical upper limits
  23. GRB241001A: REM optical/NIR upper limits
  24. GRB 241002A: Swift/UVOT Upper Limits
  25. EP240930a: Liverpool Telescope observations
  26. GRB 241002A: LCOGT Optical Upper Limits
  27. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  28. GRB 241001A: Swift/UVOT Detection
  29. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  30. GRB 240929A: Liverpool Telescope prompt followup observations
  31. GRB 241001A: Swift-XRT observations
  32. GRB241001A: optical afterglow candidate
  33. GRB 241002A: Enhanced Swift-XRT position
  34. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  35. GRB 241002A: Swift detection of a burst
  36. GRB 240930B: Fermi GBM Observation
  37. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  38. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  39. EP240930a: EP-WXT detection of a fast X-ray transient
  40. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  41. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  42. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  43. AMON NuEM 240926A: Swift XRT Follow-up
  44. GRB 240929A : Leavitt Observatory optical upper limit
  45. Fermi GRB 240930B: Global MASTER-Net observations report
  46. IPN triangulation of GRB 240926A
  47. GRB 240825A: LBT optical observations
  48. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  49. Swift Trigger 1256950 is probably not a GRB
  50. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  51. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  52. EP240919a / GRB 240919A: SVOM/VT upper limit
  53. EP240918b and EP240918c: EP-FXT follow-up observations
  54. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  55. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  56. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  57. IPN triangulation of GRB 240918B
  58. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  59. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  60. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  61. LIGO/Virgo S240919bn: GOTO optical upper limits
  62. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  63. GRB 240918B: AstroSat CZTI detection
  64. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  66. EP240913A/GRB 240913C: AbAO optical upper limit
  67. EP240919a / GRB 240919A: Mondy optical upper limit
  68. EP240913a/GRB 240913C: 1.6m Mephisto observations
  69. EP240918a: SVOM/VT upper limit
  70. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  71. EP240919a / GRB 240919A: REM optical and NIR upper limits
  72. EP240918b and EP240918c: Optical upper limits with Kinder observations
  73. GRB 240414A: further radio observations with the VLA
  74. EP240919a: Optical upper limit with Kinder observations
  75. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  76. GRB 240910A: radio detection with the VLA
  77. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  78. EP240919a: NOT and Gemini optical observations
  79. EP240919a: GOTO optical upper limits
  80. EP240919a: JinShan optical upper limits
  81. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  83. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  84. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  85. GRB 240910A: further Swift observations and confirmation of afterglow
  86. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  87. EP240918a: JinShan optical upper limits
  88. EP240918a: Optical upper limits with Kinder observations
  89. EP240918a: GMG Optical Upper Limit
  90. EP240918a: an X-ray transient detected by Einstein Probe
  91. GRB 240916A: NOT optical observation
  92. IPN triangulation of GRB 240913C / EP 240913a
  93. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  94. GRB 240821A: radio observation with the VLA
  95. GRB 240916A: Swift-XRT afterglow detection
  96. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  98. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  99. EP240913a: VLT/HAWK-I near-infrared upper limits
  100. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate

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