I'm happy to announce that the data of the photoabsorption
experiment has been pubblished in:
M.Mirazita et al. Phys. Lett. B 407 (1997) 225.
"Total hadronic photoabsorption on carbon and
lead in the shadowing threshold region"
As probably many of you already know, the photoabsorption
measurement, originally proposed and approved at TJNAF in 93,
as part of the PR-93-019, was performed last year on the SAPHIR
photon beam in Bonn.
This change was done for scheduling problems.
You can find data, informations and related bibliography
in http://hermes.lnf.infn.it/~bianchi/pan.html
The experiment clearly showed a reduction of the
absolute value of the photonuclear cross section
respect the photonucleon one, in the measured energy range,
thus suggesting a low energy onset of the shadowing effect.
This effect could be strongly related to the nuclear medium
modifications of nucleon resonances and vector mesons.
Therefore it will be very important if the TJNAF photofission
measurement will confirm in an indipendent way this exciting
experimental finding.
Regards
Nicola Bianchi
-----------------------------------------------------------
Nicola Bianchi |e-mail Nicola.Bianchi@lnf.infn.it
INFN-LNF | Bianchi@hermes.lnf.infn.it
via E.Fermi 40 |URL http://hermes.lnf.infn.it/~bianchi/
00044 Frascati |phone +39-6-94032320
(Roma) ITALY |fax +39-6-94032559
-----------------------------------------------------------