[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: 'Dirty Bomb' Was Major New Year's Worry
Having both detectors will indeed allow separation of neutrons and
gamma.
Resolution of the scintillation detectors is nowhere near to what is
needed to make a qualitative assessment of the gamma source.
It may be because I have been designing various top-performance
high resolution spectroscopy devices for quite some time now I just
cannot think of a scintillation based device as of something
"highly sensitive". Which does not mean it is not good enough,
it depends on what quantities they are after and how much noise
they get from various sources they are not interested in.
Dimiter
--------------------------------------------------------------------
Dimiter Popoff
Transgalactic Instruments, Gourko Str. 25 b, 1000 Sofia, Bulgaria
http://transgalactic.freeyellow.com
> From: "Morgan, Ben" <ben.morgan@pgnmail.com>
> To: "'Dimiter Popoff'" <k.merritt@larc.nasa.gov>, radsafe@list.Vanderbilt.Edu
> Subject: RE: 'Dirty Bomb' Was Major New Year's Worry
> Date: Thu, 8 Jan 2004 11:11:42 -0500
>
> Dimiter:
> Here are the description and specifications for a device available
> from Thermo Electron. www.thermo.com/rmp
> Regards,
>
> Ben
>
> ben.morgan@pgnmail.com
>
> The PM1401GN pocket-sized instrument is designed as a highly sensitive
> measurement device that may be conveniently worn on a belt to provide
> warning of rising levels of gamma and neutron radiation. These units
> are typically used to search for, detect and locate radioactive materials
> in a variety of situations. They also provide an excellent tool for
> extending stationary monitoring systems to expand the surveillance
> or to verify alarms of such systems and locate the offending item(s).
> Compared to the smaller pager size devices, the larger pocket-size
> PM1401GN offers enhanced sensitivity thereby increasing the chance
> of detection. Another key feature provided is early warning capability
> and audible annunciation.
>
> Detectors
>
> The PM1401GN utilizes two separate detectors, one for gamma and another
> for neutrons. A CsI(TL) scintillation detector senses gamma emitting radioactive
> materials with energies between .06 and 3.0 MeV with a useful detection
> range of 0.05 to 40 5Sv/h (5 to 40 5R/h). The neutron detector is a 3He
> counter tube sensitive to neutrons between thermal and 14 MeV.
>
> Controls
>
> A single push-button provides access to all the necessary functions of
> this user-friendly design. A second button lights the display for use
> in dark ambient conditions. These detection devices include an integral
> vibrator which may be set by the user to activate any time an alarm setpoint
> is exceeded.
>
> PM1401GN Specifications
> Gamma Detector: CsI (Tl) scintillator.
> Measurement Range: 0.05 to 40 5Sv/h (5 - 4000 5R/h). Equivalent dose rate 137Cs.
> Energy Range: 0.06 to 3.0 MeV.
>
> Neutron Detector:
> 3He Counter tube with mixture of 3He (8 atmospheres) and argon (2 atmospheres)
> Energy Range: Thermal to 14 MeV.
>
> General
> Measurement Time: 0.25 seconds.
> Detection Sources: Meets ITRAP (Illicit Trafficking Radiation Detection Assessment Program).
> Alarm Types: Audio tone and/or vibration.
> Power Requirements: One AA size battery. Life expectancy is approximately 600 hours.
> PC Communications: IR-interface.
> Data Collection: 900 data points stored in non-volatile memory.
> Operating Temperature: -300 to +500 C (-220 to +1220 F).
> Water Tightness: IP67 (optional water resistance to 20 meters)
> Drop Test: 0.7 m (27.5 inches) onto concrete surface.
> Dimensions: 97 x 57 x 32 mm (3.8 x 2.2 x 1.2 inches). Not including clip.
> Weight: 365 g (12.9 oz). Including battery.
>
> -----Original Message-----
> From: Dimiter Popoff [mailto:k.merritt@larc.nasa.gov]
> Sent: Thursday, January 08, 2004 10:05 AM
> To: radsafe@list.vanderbilt.edu
> Subject: Re: 'Dirty Bomb' Was Major New Year's Worry
>
>
> Do you actually know what their instrumentation is or is this just another summary of the kind "it is OK because it just has
>
> Dimiter
> ************************************************************************
> You are currently subscribed to the Radsafe mailing list. To
> unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu Put the
> text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,
> with no subject line. You can view the Radsafe archives at
> http://www.vanderbilt.edu/radsafe/
>
************************************************************************
You are currently subscribed to the Radsafe mailing list. To
unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu Put the
text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,
with no subject line. You can view the Radsafe archives at
http://www.vanderbilt.edu/radsafe/