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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32693 results found.

  1. XRF 030723: Detection of a rebrightening in the optical afterglow
  2. GRB030725: Optical observations
  3. XRF030723, BVRcIc field photometry update
  4. GRB021206 optical counterpart upper limit
  5. XRF030723: Re-analysis of ROTSE-III early images
  6. IPN triangulation of GRB030725 (=H2779; small error box)
  7. XRF030723 (=H2777): Second Epoch Magellan Observations
  8. GRB 030725: optical observations.
  9. GRB030725, optical transient observations
  10. XRF030723 Radio Observations
  11. XRF 030723: confirmation of fading optical counterpart
  12. XRF030723(=H2777): Chandra Observations
  13. XRF 030723: VLT spectra
  14. Magellan Observations of XRF030723 (=H2777)
  15. GRB030723: Upper limits from historical observations
  16. GRB030725, possible optical transient
  17. XRF030723: Palomar observations and proposed counterpart
  18. GRB030725 (=H2779): A Bright GRB Localized by HETE
  19. XRF030723: optical observations
  20. XRF030723 (= H2777): Chandra Observations Scheduled
  21. XRF030723, BVRcIc field photometry
  22. XRF030723, optical observations
  23. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  24. Konus-Wind detection of the bursts from SGR1806-20 region
  25. SGR 1806-20, submm observations
  26. RXTE PCA Observations of SGR1806-20 Region
  27. GRB030329: Subaru Optical Spectroscopy
  28. Triangulation of GRB030715 (single large error box)
  29. Triangulation of GRB030714 (single large error box)
  30. GRB030329: RTT150 optical observations
  31. GRBlog: Compilation of all GCN Circ. data
  32. GRB030706 triangulation (single large error box)
  33. GRB030329, optical observation in May
  34. IPN triangulation of GRB030626 (single large error box)
  35. GRB030418: R optical observations
  36. Final IPN error ellipse for GRB021206 (the polarized GRB)
  37. GRB 021206, Radio afterglow candidate
  38. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  39. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  40. GRB 030528: Optical Observations
  41. GRB 030528: tentative NIR counterpart
  42. GRB 030528, radio observations
  43. GRB030329, further radio observations at GMRT
  44. GRB030528, BVRI field photometry
  45. GRB030329, SPM optical observations
  46. GRB030528: Chandra TOO Planned
  47. GRB 030519B: optical observations.
  48. GRB 030329: optical observations
  49. GRB 030329/SN 2003dh: Jitter Episode
  50. GRB 030528, Teramo optical observation
  51. GRB 030528 Bisei optical observation
  52. GRB030528 (H2724): A long GRB localized by HETE
  53. GRB 030329: Correction to GCN 2254
  54. GRB 030329: Optical Observations
  55. GRB 030416: Optical Observations
  56. GRB030329, Optical observations
  57. GRB 030329/SN 2003dh: Possible increase in brightness
  58. GRB 030329: HST ACS Observations of the Host
  59. GRB 030329 Optical Observations
  60. GRB030329: XMM-Newton observation
  61. GRB030324: Further Observations of the Candidate Optical Afterglow
  62. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  63. IPN triangulation of GRB030519B=H2716 (small error box)
  64. GRB 030418: Second Epoch Optical Observations with Magellan
  65. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  66. HETE GRB030329, correction to Rc Observations in Loiano
  67. GRB 030329: Optical limit (contemporaneous imaging)
  68. GRB 030501: final TAROT limits
  69. IPN triangulation of GRB030509 (small errror box)
  70. IPN triangulation of GRB030509 - correction
  71. GRB030329: RTT150 optical observations
  72. GRB030329, BVRI photometry
  73. GRB030429, refiend optical brightness
  74. GRB 030329: Optical limit (contemporaneous photography)
  75. GRB030418, BVRcIc field photometry
  76. GRB 030429: Redshift of neighbor galaxy
  77. GRB030429, BVRcIc field photometry
  78. GRB030429: RTT150 optical obs., correction to GCN 2208
  79. GRB 030329: High-Resolution Spectroscopy of the Host
  80. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  81. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  82. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  83. GRB030429: RTT150 optical observations, a possible host galaxy
  84. GRB030329: RTT150 optical observations and upper limit for a host
  85. GRB030501, optical observation
  86. GRB030501 observation report
  87. GRB030501 triangulation (correction to GCN 2194)
  88. GRB030329: RTT150 optical observations and upper limit for a host
  89. GRB 030429: Radio Observations
  90. GRB 030429: redshift from VLT spectroscopy
  91. GRB 030429: IR photometry with IRSF/SIRIUS
  92. GRB030501B triangulation (single error box)
  93. GRB 030329 Optical Observations
  94. GRB030328, optical observation
  95. GRB 030329, BVRI photometry
  96. GRB030429: Optical Observations
  97. GRB030501: TAROT candidate afterglow present in archival images
  98. GRB 030501: TAROT possible candidate counterpart
  99. IPN triangulation of GRB030501 (IBIS event; annulus)
  100. GRB 030429: confirmation of afterglow candidate

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