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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').
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"

24373 results found.

  1. GRB 030824: Candidate Follow-Up
  2. XRF030824: Second-epoch Palomar observations
  3. GRB030823: optical observations
  4. GRB030823: Palomar observations
  5. XRF030824: Palomar observations
  6. GRB030823: optical observation at Tokyo Tech
  7. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  8. Summary of recent IPN and HETE detections of SGR bursts
  9. IPN detection of continued activity from SGR1806-20
  10. SGR 1808-20 (=H2802): A Possible new SGR
  11. IPN/HETE summary of recent bursts from SGR1806-20
  12. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  13. XRF030723: Re-analysis of ROTSE-III early images
  14. XRF030723 (=H2777): Second Epoch Magellan Observations
  15. GRB030725, possible optical transient
  16. XRF030723: Palomar observations and proposed counterpart
  17. GRB030725 (=H2779): A Bright GRB Localized by HETE
  18. XRF030723, BVRcIc field photometry correction
  19. XRF030723, ROTSE-III Early Observations
  20. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  21. Konus-Wind detection of the bursts from SGR1806-20 region
  22. IBAS GRB Alerts 969 970
  23. SGR 1806-20, submm observations
  24. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  25. IPN triangulation of GRB030717 (annulus)
  26. 030716 NOT a GRB
  27. 030629 NOT a real GRB
  28. GRB030329: second XMM-Newton observation
  29. GRB030418: R optical observations
  30. GRB 030528: tentative NIR counterpart
  31. GRB030329, further radio observations at GMRT
  32. MASTER: optical observation GRB030601
  33. GRB030528(=H2724): Revised SXC Localization
  34. GRB 030329/SN 2003dh: Jitter Episode
  35. GRB 030528, Teramo optical observation
  36. GRB030528 (H2724): A long GRB localized by HETE
  37. GRB 030329: Correction to GCN 2254
  38. GRB 030329: Optical Observations
  39. GRB 030416: Optical Observations
  40. GRB030329, Optical observations
  41. GRB 030329/SN 2003dh: Possible increase in brightness
  42. GRB 021004: HST observations
  43. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  44. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  45. GRB 030329: Optical limit (contemporaneous imaging)
  46. GRB030329, BVRI photometry
  47. GRB 030329: Optical limit (contemporaneous photography)
  48. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  49. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  50. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  51. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  52. GRB030501, optical observation
  53. GRB030501 triangulation (correction to GCN 2194)
  54. GRB 030329 Optical Observations
  55. GRB030328, optical observation
  56. GRB 030329, BVRI photometry
  57. IPN triangulation of GRB030501 (IBIS event; annulus)
  58. GRB030501 localized by INTEGRAL
  59. IPN triangulation of GRB030428 (two large error boxes)
  60. GRB 030429: ROTSE-III observations
  61. GRB030329 observed as a sudden ionospheric disturbance (SID)
  62. IPN triangulation of GRB030426 (annulus)
  63. GRB 030329: optical spectropolarimetry at VLT
  64. GRB030329, optical observation
  65. MASTER:optical observations GRB030416
  66. ROTSE-III prompt optical detections of GRB 030418
  67. GRB 030418: Optical afterglow candidate
  68. GRB030329: Optical Observations
  69. GRB030329, UBVRI polarimetry, R-polarization
  70. GRB 030329: SARA Optical Observations
  71. OT GRB 030329: early spectrum
  72. GRB030324: Candidate Optical Afterglow
  73. Superluminal motion in GRB 030329 (Correction)
  74. Superluminal motion in GRB 030329
  75. GRB 030329 and SN 2003dh
  76. GRB 030329 VLBA Observations
  77. GRB030328, UBVRcIc field photometry
  78. GRB 030329: possible color change
  79. GRB030329: RTT150 optical observations
  80. GRB030329: Kiso B and R band observations
  81. GRB030329: More AAVSO VR obs
  82. GRB 030329: SARA Optical Observations
  83. GRB 030329: SARA Optical Observations
  84. GRB030329: Optical observations
  85. GRB030329, cessation of fading
  86. GRB 030329: SARA Optical Observations
  87. GRB030329, optical observation
  88. GRB030329, optical observation
  89. GRB030329, new UBVRcIc field photometry
  90. GRB 030329, light curve and SN prediction
  91. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  92. GRB030329: Optical observations at Teramo
  93. GRB 030329: Radio observations at GMRT
  94. Further AAVSO V,B,R observations of GRB030329
  95. GRB 030329: Observations with ANDICAM
  96. GRB030329: Optical observations
  97. GRB030329 - OT rebrightens
  98. AAVSO V & R observations of GRB030329
  99. GRB 030329: optical observations
  100. GRB030329: Optical observations

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