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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"

32692 results found.

  1. GRB030725: Optical observations
  2. XRF030723, BVRcIc field photometry update
  3. GRB021206 optical counterpart upper limit
  4. XRF030723: Re-analysis of ROTSE-III early images
  5. IPN triangulation of GRB030725 (=H2779; small error box)
  6. XRF030723 (=H2777): Second Epoch Magellan Observations
  7. GRB 030725: optical observations.
  8. GRB030725, optical transient observations
  9. XRF030723 Radio Observations
  10. XRF 030723: confirmation of fading optical counterpart
  11. XRF030723(=H2777): Chandra Observations
  12. XRF 030723: VLT spectra
  13. Magellan Observations of XRF030723 (=H2777)
  14. GRB030723: Upper limits from historical observations
  15. GRB030725, possible optical transient
  16. XRF030723: Palomar observations and proposed counterpart
  17. GRB030725 (=H2779): A Bright GRB Localized by HETE
  18. XRF030723: optical observations
  19. XRF030723 (= H2777): Chandra Observations Scheduled
  20. XRF030723, BVRcIc field photometry
  21. XRF030723, optical observations
  22. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  23. Konus-Wind detection of the bursts from SGR1806-20 region
  24. SGR 1806-20, submm observations
  25. RXTE PCA Observations of SGR1806-20 Region
  26. GRB030329: Subaru Optical Spectroscopy
  27. Triangulation of GRB030715 (single large error box)
  28. Triangulation of GRB030714 (single large error box)
  29. GRB030329: RTT150 optical observations
  30. GRBlog: Compilation of all GCN Circ. data
  31. GRB030706 triangulation (single large error box)
  32. GRB030329, optical observation in May
  33. IPN triangulation of GRB030626 (single large error box)
  34. GRB030418: R optical observations
  35. Final IPN error ellipse for GRB021206 (the polarized GRB)
  36. GRB 021206, Radio afterglow candidate
  37. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  38. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  39. GRB 030528: Optical Observations
  40. GRB 030528: tentative NIR counterpart
  41. GRB 030528, radio observations
  42. GRB030329, further radio observations at GMRT
  43. GRB030528, BVRI field photometry
  44. GRB030329, SPM optical observations
  45. GRB030528: Chandra TOO Planned
  46. GRB 030519B: optical observations.
  47. GRB 030329: optical observations
  48. GRB 030329/SN 2003dh: Jitter Episode
  49. GRB 030528, Teramo optical observation
  50. GRB 030528 Bisei optical observation
  51. GRB030528 (H2724): A long GRB localized by HETE
  52. GRB 030329: Correction to GCN 2254
  53. GRB 030329: Optical Observations
  54. GRB 030416: Optical Observations
  55. GRB030329, Optical observations
  56. GRB 030329/SN 2003dh: Possible increase in brightness
  57. GRB 030329: HST ACS Observations of the Host
  58. GRB 030329 Optical Observations
  59. GRB030329: XMM-Newton observation
  60. GRB030324: Further Observations of the Candidate Optical Afterglow
  61. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  62. IPN triangulation of GRB030519B=H2716 (small error box)
  63. GRB 030418: Second Epoch Optical Observations with Magellan
  64. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  65. HETE GRB030329, correction to Rc Observations in Loiano
  66. GRB 030329: Optical limit (contemporaneous imaging)
  67. GRB 030501: final TAROT limits
  68. IPN triangulation of GRB030509 (small errror box)
  69. IPN triangulation of GRB030509 - correction
  70. GRB030329: RTT150 optical observations
  71. GRB030329, BVRI photometry
  72. GRB030429, refiend optical brightness
  73. GRB 030329: Optical limit (contemporaneous photography)
  74. GRB030418, BVRcIc field photometry
  75. GRB 030429: Redshift of neighbor galaxy
  76. GRB030429, BVRcIc field photometry
  77. GRB030429: RTT150 optical obs., correction to GCN 2208
  78. GRB 030329: High-Resolution Spectroscopy of the Host
  79. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  80. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  81. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  82. GRB030429: RTT150 optical observations, a possible host galaxy
  83. GRB030329: RTT150 optical observations and upper limit for a host
  84. GRB030501, optical observation
  85. GRB030501 observation report
  86. GRB030501 triangulation (correction to GCN 2194)
  87. GRB030329: RTT150 optical observations and upper limit for a host
  88. GRB 030429: Radio Observations
  89. GRB 030429: redshift from VLT spectroscopy
  90. GRB 030429: IR photometry with IRSF/SIRIUS
  91. GRB030501B triangulation (single error box)
  92. GRB 030329 Optical Observations
  93. GRB030328, optical observation
  94. GRB 030329, BVRI photometry
  95. GRB030429: Optical Observations
  96. GRB030501: TAROT candidate afterglow present in archival images
  97. GRB 030501: TAROT possible candidate counterpart
  98. IPN triangulation of GRB030501 (IBIS event; annulus)
  99. GRB 030429: confirmation of afterglow candidate
  100. GRB030425: CrAO optical observation

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