Here are some notes from our last meeting which was April 15.  
 
We had a first meeting of the ad-hoc group at BNL to examine the forward physics that Jonathan had presented   a couple of weeks ago. 
 
The meeting was attended by 
A. Tricoli, M. Begel, K. Assamagan,   B. Marciano,  H. Davoudiasl,  Xin Qian, Chao Zhang, David Asner,  Gabriella Carini,  J. Stewart  
 
The discussion was wide ranging.   We focused on the BSM physics and Neutrino physics as driving motivations.   We need to understand more about the BSM physics reach compared to other projects.  Hooman provided an overview of 
the physics models that lead to the dark photon schemes.  
 
Hooman, Bill, and others remarked that compared to other ideas, the unique element is the availability of the  neutrino data set if it can be obtained with enough statistics.   
 
Allessandro stated that there could be good opportunities for detector development in synergy with Atlas.   Many observations were made regarding the distance and the timeline for constructing the FPF.  In particular, 612 meters could cause difficulty if there is a real physics case  to tie into ATLAS data acquisition.  
 
(Some response to the 612 meters:  So far, for FASER and FASERnu  have not identified any physics where linking up with ATLAS data is helpful.  We only use their clock and their integrated luminosity. )  
 
We will meet again before the next FPF workshop on May 27-28. 
 
For the next meeting, we would like to see a table of fluxes for various relevant particle types for this physics.  If possible also some more plots and narrative on BSM physics reach.  
 
(Feng: For the BSM physics case, that is, searches for LLPs, there is, I think, a nice summary at "FASER's Physics Reach for Long-Lived Particles" [arxiv:1811.12522 hep-ph].  For fluxes of new particles, there are plots there, but also we can provide some.  Felix is also working now on a summary paper of neutrino fluxes which could be helpful.)