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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"
body:"GRB"
submitter:"Judith Racusin"

43677 results found.

  1. GRB 151029A: GROND afterglow observations
  2. GRB 151029A: Swift detection of a burst with an optical counterpart
  3. GRB 151027A: SAO RAS optical observations
  4. GRB 151027B: LCOGT FTN afterglow observations
  5. GRB 151027A: NOT optical and NIR observations
  6. GRB 151027A: T100 observations
  7. GRB 151027B: Swift/UVOT Upper Limits
  8. Konus-Wind observation of GRB 151027A
  9. GRB 151027B: Swift-BAT refined analysis
  10. GRB 151027B: RATIR Observations
  11. GRB 151027B: MASTER-NET early OT detection
  12. GRB 151027A: LCOGT-McDonald afterglow observations
  13. GRB 151027B: Swift-XRT refined Analysis
  14. GRB 151027A: VLA detection
  15. GRB 151027B: GROND Optical/NIR Afterglow Detection
  16. GRB 151027B: VLT/X-shooter redshift
  17. GRB 151027B: Enhanced Swift-XRT position
  18. GRB 151027A: THO optical observations
  19. GRB 151027A: UVOT Observations
  20. GRB 151027B: NOT optical afterglow candidate
  21. LIGO/Virgo G194575 : RATIR Observation of La Silla - QUEST Candidate
  22. GRB 151027B: Swift detection of its 1000-th burst
  23. LIGO/Virgo O1 extended until January 12
  24. LIGO/Virgo G194575: iPTF Optical Transient Candidates
  25. GRB 151027A: Swift-BAT refined analysis
  26. GRB 151027A: Early RAPTOR Observations
  27. LIGO/Virgo G194575: MASTER Optical Inspection
  28. GRB 151027A: GMG observation
  29. GRB 151027A: Fermi GBM observation
  30. GRB 151027A: MITSuME Akeno Optical observation
  31. GRB 151027A: Swift-XRT refined Analysis
  32. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  33. LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
  34. GRB 151027A: Keck/HIRES redshift
  35. LIGO/Virgo G194575: GROND multi-color observations
  36. LIGO/Virgo G194575: further Pan-STARRS observations of the RA=1hr localisation region
  37. Tentative redshift for GRB 151027A from Swift-XRT data
  38. GRB 151027A: Enhanced Swift-XRT position
  39. GRB 151027A: P60 afterglow confirmation and rebrightening
  40. GRB 151027A : ISON-NM early optical detection
  41. GRB 151027A: KAIT optical afterglow confirmation
  42. GRB 151027A: Swift detection of a burst with a bright optical afterglow
  43. LIGO/Virgo G194575: ASKAP followup
  44. LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
  45. GRB 151006A: CALET Gamma-Ray Burst Monitor detection
  46. LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
  47. GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
  48. LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
  49. LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
  50. GRB 151023A: Swift-BAT refined analysis
  51. LIGO/Virgo G194575: Pi of the Sky observations
  52. LIGO/Virgo G194575: MAXI/GSC observations
  53. LIGO/Virgo G194575: Swift observations
  54. GRB 151022A: OSN optical upper limit
  55. GRB 151023A: RATIR Observations
  56. GRB 151023A: Swift-XRT refined Analysis
  57. GRB 151023A
  58. LIGO/Virgo G194575: CQUEAN/LOAO observations
  59. GRB 151023A: Enhanced Swift-XRT position
  60. Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575
  61. LIGO/Virgo G194575: LOFAR follow-up
  62. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  63. LIGO Virgo G194575: MWA Observations
  64. LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission
  65. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  66. GRB 151022A: Swift-BAT refined analysis
  67. LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
  68. GRB 151023A: Swift detection of a burst
  69. GRB 151022A: RATIR Upper Limits
  70. GRB 151022A: Swift-XRT refined Analysis
  71. LIGO/Virgo G194575: Fermi GBM Observations
  72. LIGO/Virgo G194575: transients from Pan-STARRS in the RA=1hr localisation region
  73. GRB 151022A: Enhanced Swift-XRT position
  74. LIGO Virgo G194575: TZAC TAROT observations
  75. LIGO/Virgo G194575: Identification of a GW CBC Candidate
  76. GRB 151022A: Mondy optical upper limit
  77. GRB 151022A: MITSuME Okayama Ks-band upper-limit
  78. GRB 151022A: Kanata/HOWPol optical observation
  79. GRB 151022A: Prompt enhanced Swift-XRT position
  80. GRB 151022A: MASTER-Ural observations
  81. GRB 151022A: Swift detection of a burst
  82. GRB 151021A: MITSuME Okayama Ks-band upper-limit
  83. GRB 151021B: Fermi GBM detection
  84. Konus-Wind observation of GRB 151021A
  85. GRB 151021A: Swift/UVOT Detection
  86. GRB 151021A: Swift-XRT refined Analysis
  87. GRB 151021A: Swift-BAT refined analysis
  88. GRB 151021A: Enhanced Swift-XRT position
  89. GRB 151021A: MASTER-NET bright OT detection
  90. GRB 151021A: Optical counterpart and redshift from X-shooter
  91. GRB 151021A: Swift detection of a burst
  92. LIGO/Virgo G184098: LOFAR follow-up
  93. GRB 151004A: Swift-XRT follow-up observations
  94. GRB 151006A: Astrosat CZTI detection
  95. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  96. LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
  97. Fermi GBM trigger 466602792/151015495 is not a GRB
  98. LIGO/VIRGO G184098 : PESSTO classifications of PanSTARRS transients in the northern region
  99. Fermi GBM trigger 466316973/151012187 is not a GRB
  100. GRB 151006A: Mondy optical upper limit

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