Quick Questions and Answers
What is RARAF?
RARAF is a facility for radiobiological research with ionizing
radiations such as protons, alpha particles, neutrons and soft
X-rays. Its overall objective is to provide users with well-defined
radiation beams, which can be used as a probe of biological structure
Who uses RARAF?
Because it is the only such facility in the U.S., RARAF is extensively
used by the radiation research community, both for basic scientific
research (in which particulate radiations are used as highly-defined
probes), and for pragmatic research, such as the fields of radon
and space radiation effects.
Where can I read about the research performed at RARAF?
A list of papers that reference RARAF is available for those
interested. Some more recent papers about the microbeam facility
and research are available online in Adobe PDF format here.
What facilities are available at RARAF?
RARAF has a 5 MV Singletron Accelerator, which produces beams
of positive light ions. These charged particles are used to irradiate
biological materials directly, or to produce monoenergetic neutrons or x-rays
that irradiate the biological material. RARAF also provides users
with facilities and services such as dosimetry and microdosimetry,
cell culture laboratories, x-ray machines, and advanced imaging techniques.
What's special about the Columbia microbeam?
The single-particle microbeam facility at RARAF is fully automated.
It is possible to expose individual cells to an exact number of
α-particles, including one, at a rate of more than one cell per second.
This speed has allowed large experiments to be performed with
mutation and oncogenic transformation as the biological endpoints,
as well as all lethality and chromosomal aberration endpoints.
This unique facility has made it possible to perform experiments
that directly challenge some long-standing dogmas of radiation
biology. For example, it has been possible to demonstrate clearly
the existence of a "bystander effect" for both mutation
and oncogenic transformation. The bystander effect is defined
to be a biological effect in cells that are not themselves traversed
by a charged particle but that are close neighbors of cells that
What is the long-term goal of RARAF?
The long-term goal of RARAF is to provide those state-of-the-art
radiation sources, which can be used to address contemporary biological
questions. In general, because of the precise dosimetry achievable
with these radiation sources, radiations can act as unique probes
into biological function.
How has RARAF been made more user-friendly?
From many years of experience using RARAF as a tool for visiting
biologists, we are strongly aware of the need for support staff
and facilities. RARAF has two dedicated biology labs, containing
six cell handling benches, seven incubators, a Coulter counter,
pH meters, balances, distilled water generator, sterilizers, water
baths, and several microscopes. These labs are a few seconds walk
from the irradiation areas. The facility also has a fully equipped
workshop with four experienced machinists, who routinely design
and build specialized instrumentation. Finally, to supplement
biology experiments undertaken at this technologically complex
facility, RARAF provides a staff experienced in providing consultation
and technical assistance to facility users.
What is the schedule at RARAF this month?
The current monthly schedule is available in
How can I get an experiment request form?
Please contact Steve Marino, the manager of the facility, at
(914) 591-9244, to discuss the proposed experiment, and read the
instructions before filling out the experiment request form. Once
an experiment is approved, it will also be necessary to complete
and return the experiment scheduling form, for which instructions
are also available.