1. Milagro Jordan Goodman NSF July 2007 The History of Milagro Jordan A. Goodman University of Maryland

2. Milagro Jordan Goodman NSF July 2007 Milagro was proposed in 1990 –Before EGRET and the Compton Observatory –Before BATSE –Whipple – 10m Only one confirmed source and no spectrum Lot’s of spurious observations

3. Milagro Jordan Goodman NSF July 2007 State of the Field Measurements of the Crab

4. Milagro Jordan Goodman NSF July 2007 Milagro History 1990 Proposal Submitted to NSF for a $2.7M Detector 1994 Funding begins toward a $2.7M Project (80%NSF 20%DoE) 1995 Site Preparation - New liner & cover - PUB - Counting House - PMT structure installed 1995 -1996 Milagrisimo run - 38 tubes on pond bottom 1996-1997 Milagrito installed - Data taking begins Feb 1997 1997 Lightning protection system 1998 Milagro tubes installed, modifications to electronics, cover, water system completed (based on Milagrito experience) Winter 1999 Begin data taking with Pond only (NSF contribution $2.3M) Outrigger funding began in FY02 – finished FY04

5. Milagro Jordan Goodman NSF July 2007 Why we need Outriggers (Slide Circa 10/98) What are outriggers? –An array of water tanks outside the pond –We have built & operated a prototype –Outriggers were part of the original Milagro proposal Outriggers are essential for locating core position –Need counters outside the pond to tell if cores are inside or outside Energy Determination needs core position –Need core to determine shower size and lateral distribution - This is vital for AGNs and GRBs Angular Resolution –Curvature correction needs core position Proton/Gamma Discrimination –Proton showers trigger further from the pond –Gammas trigger more often on the pond

6. Milagro Jordan Goodman NSF July 2007 Original Milagro Design (from proposal) outriggers

7. Milagro Jordan Goodman NSF July 2007 Angular Resolution Pre-outrigger Ang res = 0.70° Post-outrigger Ang res = 0.41° From Proposal

8. Milagro Jordan Goodman NSF July 2007 Milagro Sensitivity (from proposal) Current Performance on the Crab (median E~12TeV) ~12  /yr with  /h separation and weighting ~4  /yr without  /h separation and weighting

9. Milagro Jordan Goodman NSF July 2007 Original Cost Estimate Starting in FY 91 (October 1990)

10. Milagro Jordan Goodman NSF July 2007 Construction Funding Profile Initial Pond Construction Outriggers Total Cost of Construction $2.8M (NSF) $0.6M DoE = $3.4M Plus significant lab contributions (Pond, Trailers, Lightning Protection (UCDRD))

11. Milagro Jordan Goodman NSF July 2007 Had Milagro Been Fully Funded in 1991 Construction would have been finished in 1995 instead of 2003 We would have had this data set in 1999 –We would have had full overlap with CGRO We would have been driving the field –Way ahead of HESS, MAGIC and VERITAS –At a cost of only $3M HAWC can do the same, if funded in a timely fashion

12. Milagro Jordan Goodman NSF July 2007 Problems with the Previous HAWC Review Three mail-in reviews –All had misunderstandings about Milagro, the HAWC proposal and even GLAST. Milagro saw no new sources… Large investment in Milagro did not pay off Milagro required additional funding to get outriggers in order to reach design sensitivity HAWC has a larger pond and many more PMTs than Milagro GLAST will be able to directly measure the prompt emission from the brightest bursts in the 30 MeV -300 GeV range… short time-scale variability of AGN is a very important science question - However, this is something that will be addressed by GLAST (up to energies of ~ 300 GeV) Engineering runs will not start until the third quarter of 2011 However, in order to achieve reasonable background rejection, there will be some cost to angular resolution of the detector (compared to Milagro).

13. Milagro Jordan Goodman NSF July 2007 –Two reviews showed significant bias I have never been a great fan of the use of high altitude water Cerenkov air shower arrays… [Zenith angle dependence] is fundamental problem with the technique. It is the reason Milagro should never have been built. –MGRO 1908+06 never gets higher than 30 o Since IceCube is another one of those experiments that NSF will spend lots of money on without significant science return, there won't be much that the two can do together. zero x epsilon = zero. –IceCube is already the world’s largest neutrino detector & has produced dozens of papers even while being finished. It also is using Milagro data to look at potential targets. IACTs will be covering a lot of the parameter space in complement to GLAST. Given the limited resources of funding agencies, I would think it makes more sense to support the healthy ongoing projects at this time and add resources to them to maximize the scientific output. –Wide field is critical and IACTs are working hard to do it.

14. Milagro Jordan Goodman NSF July 2007 –Those PA panel members with a good understanding of the technique likely recused themselves and were not available to pass judgment on the proposal. –Milagro/HAWC are unique as no one else does water-Cherenkov. Misunderstandings are natural. –We had no opportunity to explain or rebut any of these misunderstandings We need a dedicated committee to look at HAWC

15. Milagro Jordan Goodman NSF July 2007 Questions for Discussion 1.What will be the procedure for a panel review? a)Timing of the review b)What will be the scope? 2.How do we assure that we can be fairly reviewed by both the panel and mail-in reviews? a)What about conflicts of interest? b)What about European experts? 3.How do we deal with the uncertainty in the Mexican proposal (DoE)?

16. Milagro Jordan Goodman NSF July 2007 Questions for Discussion (continued) 4.What type of MOU will we need? 5.What should we do about an MRI proposal? a)What are the rules about asking for the support in both a regular proposal and an MRI? b)Who should be involved in the MRI (one institution or many)? c)What will the timing be of the review wrt the MRI? 6.How many pages can our proposal be? a)What may included as an appendix b)Mou’s, Mexican studies, Engineering studies, etc

17. Milagro Jordan Goodman NSF July 2007 University Grant Program Report (approved by HEPAP) The SAGs should regularize their role in reviewing projects – Each SAG should actively monitor and prioritize the experiments and R&D in its area. It should evaluate both physics goals and technical design. –The SAGs should report to P5, timing their reports so that they are available to P5 when needed. –The SAGs should review all experiments with expected construction costs above $5M, along with smaller ones seeking review. This includes both experiments that are affiliated with a U.S. laboratory and those that are not. Additional SAGs should be created as needed to cover all areas (taking care to avoid proliferation). –HEPAP should establish mechanisms for prioritizing experiments whose cost is above $5M but below the P5 threshold. The prioritization process should take advantage of input from the SAGs and should reflect the breadth of the field.

18. Milagro Jordan Goodman NSF July 2007 UGPS (cont)

19. Milagro Jordan Goodman NSF July 2007 HAWC US Collaborators Los Alamos –B. Dingus, P. Huentemeyer, G. Sinnis, G. Walker (Milagro, HIRES) University of Maryland –Aous Abdo, D. Berley, R. Ellsworth, J. Goodman, A. Smith, Vlasios Vasileiou (Milagro, IceCube) U.C. Irvine –G. Yodh (Milagro) Michigan State University –J. Linnemann (Milagro, D0) Penn State University –T. DeYoung (Milagro, IceCube) University of Utah –D. Kieda, M. Mustafa (VERITAS, Auger) U. New Hampshire –J. Ryan (Milagro, Solar Physics) University of New Mexico –J. Mathews (Auger) U.C. Santa Cruz –M. Schneider (Milagro) NASA - Goddard Space Flight Center –J. McEnery (GLAST)

20. Milagro Jordan Goodman NSF July 2007 Mexican Collaborators

21. Milagro Jordan Goodman NSF July 2007 MX HAWC collaborators

22. Milagro Jordan Goodman NSF July 2007 MX HAWC collaborators II

23. Milagro Jordan Goodman NSF July 2007