SRBL Information
Prof. Dale E. Gary Director, OVSA (973) 642-7878
Dr. Gelu M. Nita Research Fellow (973) 596-5377
Christine Oertel Admin. Asst. (973) 596-5376
Kjell Nelin Observer/Technician (760) 938-2075 x118

New Jersey Institute of Technology
Center for Solar-Terrestrial Research
323 M L King Blvd.
Newark, NJ 07102-1982
FAX: 973-596-3617

- Single, automated, 6-foot parabolic dish
- Azimuth-Elevation mount with full-sky coverage
- Chain drive and stepper motor with 7.5" increments
- Planar, log-spiral receiving element for 610 MHz and 1-18 GHz measurements
- Coplanar, interleaved Yagi for 245 and 410 MHz reception
- Frequency-agile microwave super-heterodyne receiver with 3 YIG local oscillators
- 40 ms samples, interleaved with noise-diode measurements for gain stabilization
- Nearly 600 logarithmically-spaced candidate frequencies


- Remotely operable (central location to be in Colorado)
- Computer-automated, operating several weeks at a time, unattended:
... Control PC for time-critical antenna and receiver tasking
... Analysis PC for scheduling, real-time analysis, archiving
- Independent flux calibration obtainable from lunar measurements
- Relative flux calibration from quiet sun cf. USAF RSTN measurements
- Real-time automated messaging


- All-weather, 24-hour coverage
- Radiometrically calibrated at each frequency to the ~1% level
- Scans through 120 selectable frequencies every 4.8 seconds
- Interference rejected by analysis software
- Location accuracies of <3 arcminutes (geocentric) expected for >500 sfu bursts
- Modest volume: ~3 MBytes per day per instrument


- Original project cancelled by the U.S. Air Force in 2003. Now operated by NJIT
- Software development continues
- Plan to combine data from SRBL and SRSP (operated at Bell Labs/Murray Hill facility)
- A second SRBL is planned for operation at Sac Peak, NM


SRBL was invented in 1992 at Caltech, when Dr. Gordon Hurford developed a unique burst location technique based on spectral measurements rather than interferomery or mechanical scanning. The Solar Astronomy group at Caltech then designed, built, and tested two prototypes, borrowing heavily from earlier systems operating at the Owens Valley Radio Observatory (OVRO) near Big Pine, California. The first was installed and operated at the Air Force Solar Observatory on Palehua, Hawaii; remaining there until early 1999. The second is installed at OVRO, where it continues to take solar data and is used as a test bed for system modifications and upgrades.

SRBL was originally developed under an Air Force contract to Caltech as a technical feasibility and demonstration program, to compliment the USAF Solar Optical Observing Network (SOON) in detecting and locating radio/flare activity on the solar disk during obscured visual conditions. Later, SRBL was augmented to provide a replacement for the aging and costly Radio Solar Telescope Network (RSTN). Frequency extensions were added, along with improved calibration procedures and capabilities, horizon-to-horizon coverage, remote and unattended operation, and standardized messaging capabilities.

In 1998, the USAF selected Raytheon Technical Services Company to fabricate, install, and support SRBL systems worldwide. Present Caltech activities include technical direction of the program, maintenance/operation of the OVRO prototype, and continuing development of hardware and software to make scientific/functional improvements.

The USAF mission for SRBL is to improve space weather forecasts through use of burst location and spectral information. The most likely Solar Electro-Optical Network (SEON) sites include: Palehua - Hawaii, Learmonth - Australia, San Vito - Italy, Sagamore Hill - MA, and/or Holloman - New Mexico. Data will be sent over dedicated circuits to a central facility in Coloroado, and to the NOAA Space Environmental Center in Boulder.


Solar Radio Burst Locator, (HESSI conference, 2000)

SRBL prototype evaluation, (USAF report, 2001)

Technical Review of SRBL, (internal 2001)

Statistical Correlations Between SMBs & CMEs, (ApJ 577:457, 2002)

New Jersey Institute of Technology

Dale E. Gary