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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"

32531 results found.

  1. GRB 090424: optical observations
  2. GRB 090427: GROND observations
  3. GRB 090429A: ROVOR magnitude limit
  4. ICSP VLF observation of GRB090427 from two receivers
  5. ICSP VLF observation of GRB090424 from four receivers
  6. Refined analysis of ICSP VLF observation of SGR J1550-5418 bursts on 22nd January, 2009
  7. GRB 090428B: Suzaku WAM observation of the prompt emission
  8. GRB 090424, SMARTS optical/IR afterglow monitoring
  9. GRB 090426: optical observations
  10. GRB 090429B: Swift/UVOT Upper Limits
  11. GRB 090429A: Swift/UVOT Upper Limits
  12. GRB 090429B: Gemini-N further nIR observations
  13. GRB 090424: YNAO-GMG observations
  14. GRB 090429A: Swift-XRT refined analysis
  15. GRB 090429A: GROND upper limits
  16. GRB 090429B: Swift XRT refined analysis
  17. Konus-Wind observation of very bright GRB 090427
  18. GRB 090418A BVRcIc field calibration
  19. GRB 090426: GAO 150cm telescope Optical Observation
  20. GRB 090429B: RIMOTS optical upper limits
  21. GRB 090429B: Swift-BAT refined analysis
  22. GRB 090429A: Swift-BAT refined analysis
  23. GRB 090429A - Correction to XRT position
  24. GRB090429B: Gemini-N infrared IR candidate
  25. GRB 090426: YNAO-GMG observations
  26. GRB 090429B: VLT upper limits
  27. GRB 090429B: GROND Observations
  28. GRB 090429B: Super-LOTIS early observations
  29. GRB 090429: Swift detection of a burst
  30. GRB 090423: pseudo burst at z=1 and its relation to GRB 080913
  31. GRB 090424 : Multiband Optical observation from Nainital
  32. GRB 090426: R-band limit
  33. GRB 090424: Continued R-band monitoring
  34. GRB 090423: CARMA mm observations
  35. GRB 090426: Swift/BAT spectral lag results
  36. GRB 090424: Suzaku WAM observation of the prompt emission
  37. GRB 090426: VLT spectroscopy
  38. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  39. GRB 090426: Near infrared observation with ISLE at OAO
  40. GRB 090426: Okayama MITSuME optical observation
  41. GRB090426 Swift/UVOT observations
  42. GRB 090426 Keck LRIS redshift
  43. GRB 090426: Swift-BAT refined analysis
  44. GRB 090426: Swift-XRT refined analysis
  45. GRB 090423: GROND second epoch imaging and refined SED
  46. Detection of bright radio afterglow of GRB 090424 with the VLA
  47. GRB090426: Observation for Optical counterpart from MIRO
  48. GRB 090426, RIMOTS optical upper limits
  49. GRB 090426: inspection of SDSS images
  50. GRB 090426: TNT confimation of optical counterpart
  51. GRB090424: R-band detection (37.5 hrs post-burst), jet break?
  52. GRB 090424: MASTER-Net prompt optical limit
  53. GRB 090423: Fermi GBM observation (correction of isotropic equivalent energy)
  54. GRB 090424: WHT ISIS spectroscopy
  55. VLA radio observation of high-z GRB 090423
  56. GRB090424: BVRI/R-band detection after 15 hrs burst
  57. GRB 090424 : Lulin 1m telescope optical observations
  58. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  59. GRB090423: Y-band limit
  60. GRB 090424 Gemini-South Redshift
  61. GRB 090423: Y-band field calibration update/correction
  62. GRB 090423: Swift/BAT spectral lag results
  63. GRB 090424 : TAOS optical detection
  64. GRB 090424 optical observations
  65. GRB 090424: Liverpool Telescope observations
  66. GRB 090424: Swift-XRT refined analysis
  67. GRB 090424: Optical observations from 1.23m CAHA
  68. GRB 090423: energetic, luminosity and jet break
  69. Swift/UVOT observations of GRB 090424
  70. GRB 090424: MASTER-Net prompt optical observations
  71. GRB 090424: Swift-BAT refined analysis
  72. GRB 090424: Fermi GBM Observation
  73. GRB 090423: Fermi GBM observation
  74. GRB 090422: Fermi GBM observation
  75. GRB 090423: Ep,i - Eiso correlation
  76. GRB 090424: SDSS Galaxy at the Swift position
  77. GRB 090424: TNT optical observations
  78. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  79. GRB 090423: Refined TNG analysis
  80. GRB 090423 limiting magnitudes
  81. GRB 090423: Near infrared observation at Okayama Observatory
  82. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  83. GRB 090423: TNG Amici spectrum
  84. GRB 090423: GROND detection and preliminary photo-z
  85. GRB 090423: NOT z-band limit
  86. GRB 090423: Correction to NIR photometry
  87. GRB 090423: Swift-XRT refined analysis
  88. GRB090418A Rc-band photometry
  89. GRB090423 - Swift/UVOT upper limits.
  90. GRB 090423: NIR photometry and evidence for spectral break
  91. GRB 090422: Swift-XRT refined analysis
  92. GRB090423, RIMOTS optical upper limits
  93. GRB 090423: UKIRT data further analysis
  94. GRB 090423: Swift-BAT refined analysis
  95. GRB 090422: Swift/UVOT Upper Limits
  96. GRB 090423: P60 Observations
  97. GRB 090423: Faulkes Telescope South observations
  98. GRB 090418A: R and I band observation
  99. GRB 090422: Liverpool Telescope possible candidate
  100. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis

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