Milagro meeting LAMPF Auditorium 12 -13 Feb 1997 



Index
Day 1 - June 12,1997
Cy Hoffman    What we need to accomplish today  tomorrow
Gus Sinnis  Rich Miller    Status of Milagrito  Site 
Jordan Goodman    General Budget Issues
Jordan - Planning and Timetable  (Gantt Chart)
Andy Smith et al  Status of Milagrito Reconstruction
Jordan
Gus
Isabel Leonor - Calibration
Peter Nemethy - pedestals
Rich Miller - Fibers 
Tony Shoup    PMT/cable/encapsulation status, plans
Todd Haines    Safety  Training
Michael Schneider    Water System    results, plans 
Todd    more water stuff
Linda Kelley    Electronics Status/Plans
Tony Shoup    Outrigger counters    design, cabling, fence
Cy Hoffman    Review of What We've Done Today 
David Williams    Reflectors/Baffles for PMTs 
Day 2 - June 13, 1997
Don Coyne      Cover Modifications    Needs and Plans
Cy Hoffman    Plans for work this summer 
Don Coyne    Lightning Protection System (Status)
Gus Sinnis    Milagrito Disassembly 
Morgan Wascko    Igloo Results
David Williams    Muon Layer Design Discussion 
Gus    current status of igloos 
Peter Nemethy    Peter Installation Scenario
Jordan Goodman    Review of Plans  Budgets
Stefan Westerhoff et al.    Monte Carlo Simulations 
Gaurang
Mei-li
Stefan
Discussion on Analysis  Data  Taking Strategy

Cy Hoffman  What we need to accomplish today  tomorrow
Decisions that allow us to install Milagro next summer
        Muon layer  igloos or simpler?  if igloos, what kind?
        Installation strategy  wet or dry? cover disposition?
                when to start? how long? how many people?
                how to dismantle Milagrito?
        Cables  what length?, what kind?, patch panel?
        Other changes?
What present at ICRC  moon shadow?
Milagrito analysis strategy calibrations, slewing, event fitting, Monte Carlos
Outrigger detectors design, cabling, electronics, fence
Modifications to Milagrito calibration system, PMT replacement,
  pub trailer cable plant patch panel

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Gus Sinnis Rich Miller Status of Milagrito Site Data Taking, Operations, etc
Gus 
DAQ System
  FASTBUS no problems
  VME, SGI no problems
Front End Boards
  1 fried channel (we did) ~ 4 different channels being looked into
PMTs

  10 already dead (10 more died previously and were replaced), 
1 died last week mostly infant mortality, things seem to have 
settled down

Cover   some light leaks, repaired, mostly okay 

Water system   
several problems   pumps died, water hammer, pressure too high, 
system leaked, carbon getting by the 1 micron filters, 
cannisters rusted through, water bugs failed (cold solder 
joints) leak did not turn off system   solutions pump motors 
replaced (were good, now have spares) installed flexible pvc 
from pub to pumps installed uvlamp shutoff retrofit on filter 
cannisters (there was a defect in the cannisters, sent in for 
repair)   running 200 gpm since May 16 smallest filter is 0.5Fm 
Running time 77% live time since Jan 30, or 85% if exclude the 
zeros in the last month, most down time owing to MG reset

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Rich 
Milagrito running 
  2.095e9 events, 117 DLT archive tapes, 2.34 TBytes of data
  1 tape per day
  Experiment control relatively easy web run mostly
  Shift running has been easy only one emergency, that was water problem on 28 March
  the MG set has tripped gt 5 times
  log book usage is still not totally regular he urges people to use it more frequently
Some milestones more on vugraph 
  Regular data taking started 8 Feb 1997 
  online reconstruction started 4 Apr 1997 
Made a small Milagro shift cheat sheet to attach to badges 
  need 10 minute training on how to do shift


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Jordan Goodman General Budget Issues timetable
Not a good year at the NSF. Ongoing battles with them about both construction and operations
Projected to get $584k construction, $190k operations
Has cost estimates (to finish Milagro) available on the web
  Total remaining to spend $1m, with contingency $140k
  NSF giving us 454k construction 97, + 360k next year 98 
with payback on operations (?)

  Program review? bring them on! just a threat? or an offer for 
more support? we need notice, however, and prefer that they not 
come during summer   will the NSF pay for a tech at the lab? 
they are not willing to fight that issue accepted the idea of 
0.25 tech $145k operations including utilities   we're pretty 
close but flow of money is still problematical have to defer 
some purchases until next year computers (that we don't need 
until Milagro), outrigger array, 150 PMTs (though we must have 
the money early for these may have to sit on Eisenstein 
Important we have to order the tubes by Feb 1st to have them 
by August 1st!!)

Planning and Timetable Jordan has a Gantt chart!
  Operate Milagrito thru 15 Apr 98
  Cover design study finished now (??)
  Cover mods July Oct 97
  Lightning system study done
  Lightning install June July
  Muon layer design study to be finished by end of July
  Install wiring from pub to counting house by end of summer
  Prototype outrigger array July August ~100 boxes?
  Muon layer box procurement Fall 97 what about building almost too late now
  PMT testing encapsulation by batches everything done by August 1 1998 (?)
  Electronics in by Jan Feb 98 test with readout 
  Drain pond starting 15 Apr 98
  Remove Milagrito tubes by 1 Jun 98
  Survey Grid, Clean Pond by end of Jun 98
  Install Muon/Hadron Layer by late summer (beginning July to end of August)
  Install Calibration System late summer
  Final cleaning in August
  Start filling pond by Sept 1
  EAS layer installation from raft should practice this summer to see if practical
  Continue fill through early fall
  Install outrigger array
  Debugging run including muon layer 
  Start data taking in 1 November 1998

Click here to get postscript file for the schedule" Back to index

Andy Smith et al Status of Milagrito Reconstruction
Software still has problems
10% showers fail fit losing most of the muons?
what to do about late light? small pulse heights are late by a lot (100 ns?)
resolution is still not understood, possibly a function of zenith angle
decreasing number of hit tubes for high zenith angle (shadowing of berm?, or maybe spectrum of GCR folds in? very sharp break around 50 degrees)
50% of hits fail to be included in the fit
Jordan
not ready to write papers yet still trying to understand how the detector works
We throw out a lot of tubes, and do we understand why? beautiful showers are beautiful but smaller showers are a mess if you get more than 150 tubes, you throw fewer and fewer tubes out they're all nailed (10 pe's minimum)
cooked up parameter to measure robustness of shower fit take each tube, shake the times by a Gaussian (~2.5 ns) new fit shouldn't change by much del angle between fit wiggled fit peaks at 0.5 degrees, long tail
del wiggle parameter gets much worse at zenith angles greater than 40 degrees, strong rise above 65 degrees to 2 degrees and more resolution at 53 degrees is 1.2 degrees or so
del e o exhibits similar behavior
foreshortening of array at large zenith angles is an effect that contributes to this problem
of course average trigger energy increases at large zenith angles
Gus
shows event displays with different cuts to see how the angle difference and the quality of fit depends on the cut chi sq improves with 1pe cut, more with 2pe cut and fit seems to be converging and stabilizing as cut is more severe but still get large angle changes (tail up through 14 degrees) yet del e o does not change much at the peak (though tail diminishes) we're looking at 1.5 degrees at the peak, with a long tail indicates some intrinsic in slewing, calibration, etc. Also fit larger fraction of showers when making stronger cuts.

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Isabel Leonor - Calibration

Isabel described the calibration system optics. Light is monitored by a photodiode before the filter wheel.

Data was taken at 13 filter wheel position - 4000 shots optical densities vary from 0 to 4

She describes the slewing corrections she is working on. Specifically she describes when she switches from low to high pmt. She then showed that for most channels a 3rd order polynomial fit fine but in some cases a 4th order fit much better. Some fit very poorly no matter what. She showed a map of which tubes could be best illuminated by which laser ball.

4 tubes had a bizarre relationship between falling edge time and tot.

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Peter Nemethy - pedestals

need to find timing pedestals -

A getting peds from laser calibration -

assume laserballs are at nominal location.

Get tpeds from slewing corrections and tube positions.

By using far away tubes we can reslove the ambiguity between laser ball position and pedestal ambiguity.

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Rich Miller - Fibers - A large fraction of the fibers leak light. The 6 dark cladded fibers work well. The others don't. New fiber is the answer. We need 3750m of fiber it may cost ~$1.50/meter.

There is a question as to whether we need to calibrate the igloos with a laser.

We should put some fibers in a few igloos for intercalibration.

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Tony Shoup PMT/cable/encapsulation status, plans

PMTS -We need to order 100 PMTs by Feb 1 in addition to the 200 we are ordering now to be ready


  need to finish 800 cables for the 
pond $49k   what should short cables be made of?   do we want 
to do a different cable routing pub count house? Box on outside 
might need longer quot short quot cables have to throw away the 
75 ft cables?   the cables in the pond for the air shower later 
should be 20 ft longer, 490 number   use rg 59 for the pub 
count house need 800 x 100 ft = 80,000 ft or 80 spools ?   rev 
Scott Neil will make a proposal in the next fortnight about the 
pub counthouse cables

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Todd Haines Safety Training
We have to take safety seriously, especially as regards visitors experiment could be taken down if we're not careful. It's everybody's responsibility.
Milagro site (our requirements) 
  need site specific training Gus is revising the 
  need first aid and cpr that's up to date some discussion about 
rescinding this requirement, as the courses seem tobe too trivial. 
We've decided that it is sufficient to have taken the course once, 
not necessarily that the training is current.
If you visit LANL for gt 10 days, you have to have 
  GET training (2x0.5 days or can test out)
  LANSCE site specific training
  A training plan TH will do for everyone 
  signed safety commitment
  P 23 new employee visitor checklist
In addition students must do
  student hire checklist
  have an assigned supervisor mentor
  participate in local student activities

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Michael Schneider Water System results, plans (including rainwater?)


  How are we doing? poorly at 5/16/97 pond is lt 3m at 3000C, 
but after the 1Fm filter better   Internal welds and 
feedthroughs of the filter canisters are rusting through 2 have 
been shipped back to the manufacturer to be replaced, other 2 
yet to be done   Charcoal found all over the filters did not 
seal properly in the filter cannisters retrofit has addressed 
this problem   Water at 5/20/97 shows we can make 10m water (at 
43500 C 7m at 3000 C) why? confirmed by 5/27/97 not going 
through the softener to reduce the pressure, but both 0.5Fm and 
1 Fm filters this is water going back into the pond   But how 
is the pond itself doing? 5/27/97 is overlapping original 
9/16/96 line but in the interim things were better 4/11/97 is 
highest curve, 3m at 3000C and even the 5/16/97 curve is higher 
than the latest one things going bad in just 11 days   Is 
something happening in the pond that happens faster than we 
recirculate? Chemical reactions or biology?   Propose a change 
put the sand filter (10 15Fm filter) before the charcoal 
filter to protect the charcoal from the incoming particles but 
need to protect the rest of the system from the charcoal. 
Better to take current charcoal filter, put sand into it then 
buy new, larger, tank for the new charcoal filter 62 
inches diameter rather than 48 then put a 20Fm filter in 
series with the 1Fm filter (instead of 2x1Fm filters in 
parallel). The new charcoal filter tank would be about $10k, 
electropolished onetime investment. We really need the 200 gpm 
flow (part of existing problem is that high flow breaks up the 
charcoal, so need larger tank).   Filter changes on the 20 and 
1, 0.5 must be done at the same time turn off the flow and do 
it 5 minutes job must be done every 3 4 weeks   Igloo plumbing 
quick connect at $20 per igloo delrin disconnect stops the flow 
needs 30 psi, which may be a problem for the pond filtration 
system owing to backpressure maybe a separate, simpler system 
just for the igloos, assuming that water eventually has gone 
through the pond filtration system

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Todd more water stuff
Issues
  what to do about the media filter (presently by passed because of backpressure)
  what to do about backflush from softener aren't allowed to put it on the ground
  when do we fill with more water, and how much?
Status
  softener lt 1 grain hardness ( lt 17 ppm), 40 tons NaCl
  supply pump miswiring has been fixed, we have two spare motors
  filter tanks sent for repair
  5/16/97 analysis water also sent to commercial outfit Roy at SouthCoast Pollution Control
    from 0.5 Fm, lt 1 ppm small and large
    from pond , lt 1 ppm large, 10 ppm small but this may be wrong 
contaminated with 0.3Fm particles or oil or other organics?

Back of envelope Attenuation length in cm = 13 x radius in 
microns, x density in particles per cc. If lambda is 500 cm, 
particle size 1 Fm, density must be 6e4 per cc, and total 
volume of particulates is only 2 cc was sticking to cover or 
liner, and just coming out slowly? Can we use rainwater that 
lands on the cover? Need to run it through the filtration 
system, but prior to that we need some pre filter to catch 
leaves and vermin. There are some unfinished lines, but we also 
need pump in the catchment basin the outfall on the west side 
of the pond. Can't use one of the submersible pumps, but maybe 
one of the trash pumps. Argument about what to do about 
filtration system Todd argues for understanding what is 
happening in the pond, others saying we ought to do the changes 
Michael suggests even if we don't understand what's happening 
in the pond, because it's a problem that will have to be 
addressed anyway. Everyone agrees we should change filters so 
that we have a 20Fm and 1Fm filter in series so as not to plug 
up the fine filters with junk. This may be just a valve 
configuration change not clear or have to splice in a new 
canister (not a big deal) after the multimedia filter. Or put 
in 2 of the 20Fm filters, one after the softener (as Michael 
suggests).


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Linda Kelley Electronics Status/Plans

ECL boards 2 substantial changes for solar physics 
individual scalar output header changed to low TOT, and another 
low threshold multiplicity output   there is a 5 prototype run 
that will be back by 6/20 for testing of these changes   by 
another 2 3 weeks, we should know whether further changes are 
needed     so we'll have boards this fall for testing the solar 
physics design mods

Analog boards one correction no change needed to the films or prototype 
How many boards do we make?
  total channels gt 1100 , giving ~75 boards
  we have 20 ECL, 25 Analog
  if we make 50 55 new, we'll ahve as many as we'll ever need
  ~1 month leadtime needed but 3 months if we decide we need more later (?)
  assembly cheaper houses? ECL can be done in house at UCSC, but analog has 
  too many components for that

Schedule 
  begin ECL fab ASAP ready for assy end of July
  begin Analog fab in mid July, ready for assy end of August
  use student labor in the summer, allow time for extended assembly more testing
  all boards will be ready and tested by the end of fall probably December 
  ready to install at the site in February 
Channel count 
  pond 450 + 228 + 170 = 848?
Decide to go ahead make the 55 more of both kinds of boards, 
   but defer decision of populating all of them until later


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Tony Shoup Outrigger counters design, cabling, fence 
Monitoring tanks and shmoos   in tank need to keep track of 
certain physical measurements, like temperature, water quality, 
etc. We don't know how well it's doing over time, since it's 
only been in the data stream a short time. To maintain quality 
perhaps just fill once, disinfect with hydrogen peroxide, and 
then never open again. Or considering that it's just 2500 
gallons per tank just periodically dump and renew.     Want to 
improve the mounting of the PMTs in the tank. Estimated cost 
~$350 per tank (not including shipping, made in Wisconsin, so 
shipping might be expensive).   cabling in conduit? 
certainly use old stuff (old shmoo cables)? watertight 
connectors? connector is out of the water in the present 
design, but is exposed to the atmosphere can use cheap 
connector, but with a cover (like the covers on the shmoos?)   
deployment where when, who, how   do we use shmoos? Gus would 
like to use 100 phototubes from the shmoos for the air 
Cherenkov experiment   how many shmoos, how many tanks what's 
the appropriate mixture   have a limited number of Hamamatsu 
tubes that we can put in tanks   tanks are arguably 10x better 
than shmoos so 20 tanks would be as good as all 200 of the 
shmoos tanks have further advantage in that detector physics is 
more similar to the pond   best use of shmoos is to extend to 
bigger array, higher energy how high do we want to go? if to 20 
TeV, need no shmoos at all   part of the answer should come 
from Monte Carlo studies string of pools, string of shmoos or 
patches determine optimal density of outriggers versus distance 
from the pond   use outriggers for timing? then need timing 
studies with existing outriggers is the water tank good for 
timing, or does the internal reflection kill you? first sharp 
rise time may be okay comes from first reflection on the bottom 
can correct for that 


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Cy Hoffman Review of What We've Done Today 
Calibration system
  decided to buy new fiber, continue using fiber balls
  no laser ball in every muon box, but in samples of them need deployment scheme
  cooling/heating problem in laser shack taken care of

ICRC papers
  Jordan gives first light paper
  Dave gives poster on Simo results
  moon shadow paper will become whatever we need it to be expect a miracle

PMTs
  Jordan's schedule is okay, but tight for getting last PMTs here have to pester theNSF
  not agreed how many PMTs we will have when this is over uncertainty involving couple dozen tubes

Cables   air shower layer will have 20' longer cables than we 
have now   re use the existing cables in the pond for muon 
hadron layer, but we need some 100 more and what length? not 
decided probably best same length as existing   cables from pub 
to counthouse use rg 59, and need somewhat longer cables than 
we have now. likely can't use the ones we have now, prefer 
soft, pliable cables. Use scheme of Neils to have a box under 
neath the trailer with a patch panel. Can use old Cygnus 
cables, which are a good length for this. Apparently we will 
throw away the old pub counthouse cables, which might be worth 
$5k.   patch panel design needs lightning system design before 
finalizing (conducting or not?)

Water system   decided to add a 20Fm filter upstream of the 
charcoal tank, maybe after the water softener, but will try to 
understand what's going on in the pond before reversing the 
sand and charcoal filters

Electronics   will purchase 55 ish boards, but not decided how 
many will be stuffed have another month to make that last 
decision we should be able to come up with a minimum number 
1000 channels seems right.


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David Williams Reflectors/Baffles for PMTs (advanced from tomorrow schedule)
Anecdotal evidence of bad light 
  trigger rate at 25 tubes is gt 5kHz,
  scaler rates in tubes show time structures that are sometimes seen by several tubes are there tubes that emit light? tube 177 was doing this, and has lately died, 
  acausal hits neighbors with signals separated by more than their distance
  tubes rejected from fits never early, but late might be shower light arriving at tubes from different paths than expected
So make a baffle that will limit the field of view of the tubes simple cones of Everbrite wrapped around the tubes 
  downside would cut you off at large angles calibration might be a little harder 
  also an additional reflecting surface might be a bad thing to have in the pond and you don't want to get rid of light 
Recommends doing this for a few tubes this summer to see if this gets rid of some of the bad light 
Some bad light coming through the acrylic cap on the PMTs, and this ought to be fixed at the minimum. Make the caps on the PMT opaque (now acrylic, make pvc)? But this change might cause other problems better to put an opaque barrier within.

13 Jun 1997 Fri 8 59 03



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Don Coyne Cover Modifications Needs and Plans the continuing 
saga Model not infinitely trustable dynamics ok for long 
features, ditches not modeled properly, and winches tabs in 
model are infinitely capable. Have to learn when to trust it 
and when not to. Propose flexible couplers that can free the 
line or couple the line to the membrane, spreading the force 
over a patch, and that can be assembled cheaply from readily 
available components steel D's and O's. This gives a quot 
tunable quot design, where you can adjust the pressure 
delivered to the cover and the straps. Video shows model 
stability increased with diagonal quot quilting quot straps 
(just strung across, tied at the ends, not tied to the cover) 
in general stability increases with greater tension on the 
straps. When transiting between stable modes (low cat, high 
cat, bubble), the cover is still unstable in a wind. Stability 
results from either stressing the cover or putting a fine mesh 
over it so far we've tried neither in real life. But there are 
lots of possibilities how do we choose? Prefer doing 
everything, of course, better winches, straps, connections, and 
quilt, including concrete piers for the diagonals. This option 
costs $106k. Quilt alone may work, needs no cover mods, and 
costs $32k Don is not confident enough in this one. A 
compromise would be 2 diagonals only, plus winches and cover 
mods (new tabs envelopes for some lines (~1/2), not all) for 
$50k. If all lines tabbed and enveloped, $86k . This seems 
to be the preferred option (#2). Decide contract Neal part 
cover mods, multi mode connector, for option #2. Operate in 
this mode this summer, to see if we need the diagonals, while 
at the same time pursuing the contract for the diagonals 
(mainly concrete piers, done by PM).When the contract is just 
about in place, we will be able to decide whether or not we 
really need the diagonals and proceed accordingly. Neal's part 
will necessarily happen more rapidly use the guilt factor.


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Cy Hoffman Plans for work this summer cables, water system, fence, patch panel, PMTs
On water we will do the 20F filter before C, more water studies, including trying to use rainwater. Delete this last option 
On the patch panel 
  get it out of the way of the water system
On the PMT's
  diagnose failures and replace? we should do this 
  install test the new encapsulations? also we do this 
  install test baffles reflectors? we will make some and install
  try some PMT's with opaque bases? we ought to try this too, with new glue
On cover mod's
  start with Neal mods, as discussed above
Pre installation studies
  learn how to work in water with raft  will do in changing the PMT's
Deploy more outrigger tanks
  Tony will order 16 (a 4x4 patch, or cluster plus trailers), 
labor for installation will be needed Fencing will also be an issue
Lightning system definitely much work, some shutdowns
Upgrade the calibration system Richard, at the same time as PMT re installation
Igloos ? Cut an igloo open and examine it.


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Don Coyne Lightning Protection System (Status)
Faraday cage scheme has converged
Bidders' feedback has confused some issues 
  Cu, or Cu coated steel?
  sliders? or raising cables?
  cables in the pond? decide not to do this!
Construction 5 bidders, ranging from ~100k to 200k
Perhaps deal with pros for boring climbing, and we do bonding, raising, d
itching(?) piecemeal approach using quot mountain men quot contractors 
Cable bulkhead should be metal? Actually need more tests 
Other parts of LPS left up to hardware subgroups 
Schedule DC here June 22 29 liaison with Staley ICRC takes out part of 
July August do we wait until fall?


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Gus Sinnis Milagrito Disassembly 
Drain pond
  3 million gallons @ 200 gpm  2 weeks
Remove PMTs
  take them out 2 days (put them in in one day)
  may take a little longer because pond is damp and tubes have to go 
up not down
  Re encapsulate yes, but here, not Irvine or table decision 
until we've seen some
  Remove igloos
Cables
  Leave 'em in, but seal the ends?  0 days
  seal the ends with UCI system 1 day
  rip out fibers, keep the floats
Clean Pond  
        1 week


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Morgan Wascko Igloo Results Triggered on scintillator 
paddles above below the igloo (paddles only on #1 #7), also on 
tubes (6/16) immediately surrounding the igloo. Get a result on 
paddle triggers, igloos 1 7 see 30 and 24 pe's per muon. Seven 
measurements (each a day's worth of data) in half a year show 
fair stability in igloo 1 data taking for igloo 7 has only 
recently begun.


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David Williams Muon Layer Design Discussion 
Concludes the igloos are hard to beat!
Double density hadron layer works ok.

We should choose to build the igloos, but not if cost is 
gt $1k per igloo. The denser hadron layer remains available as 
a low cost option. Results for gamma hadron separation   
With Muon Layer Counts gt 5 pe's in a muon box as a muon muon 
layer pulseheight distribution gives a very clean separation 
between hadrons gammas.   With dense hadron layer Can get a 
separation between hadrons gammas in the denser hadron layer, 
but it is much poorer. Can make quot staircase quot cut as a 
function of total number of pe's in the hadron layer   Quality 
factor at 1 TeV, schemes are indistinguishable, but above 30 
TeV, get much better separation with the muon layer We 
should install igloos as a right path for doing muons, with the 
option later of making a denser hadron layer as an enhancement 
to Milagro for lt $0.5M Possibility of using some of the extra 
tubes to make a small dense section in Milagro, but maybe we 
should just make it bigger rather than denser 58 tube increment 
(170 to 228, same as present Milagrito).

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Gus current status of igloos shoebox design, 
trapezoidal outline for stacking Central Container Company of 
CA came back with price quote description $1200 Roy has a 
different supplier, different price quote, $375 difference is 
in strength, sturdiness and thickness, cheaper one will barely 
support itself, and will need braces to support the PMT's. 
Material is all HDPE. Time to assemble after delivery Tyvek 
plus water inlet couple hrs/box How long can we wait to decide 
whether to build or buy igloos? Gus thinks we can decide in 
August. Four months may be enough time to build, but we don't 
know where to do it or how to store them.


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Peter Nemethy Peter Installation Scenario
Here's the putative schedule, most of which will occur under high catenary mode 
  Remove Milagrito  3 days/12 p
  PVC grid fixes 3 days/6 p
  pond cleanup 6 days/12 p
  survey   3 days/3 p + prof  inflated
  coax cable plant  6 days/8 p
  fiber optics conduits strings  3 days/4 p
  162 igloos install, plumbinb, anchors 12 days/12 p
  dry install muon/hadron pmt's 2 days/12 p
  sig/hv test all pmt's 2 days/4 p
    (fill to submerge)
  inspect/untangle snake dance 2 days/4 p
  replace dead pmt's  2 days/4 p
    (fill to ~4 m) (continue filling)
  wet install shower layer  10 days/12 p inflated
    (450 pmt's, 50 per day)
  sig/hv test all pmt's replace 4 days/4 p
  shakedown run with tube still floating Y
These are calculated as 10 hour working days 
Integral of working days 58, not including time for fill there are 20 working 
days per month, so this is essentially 3 months.
We need a high duty cycle lots of days when we're allowed to work, and lots of 
time working on those days. We need to be able to stay in catenary with rainspout 
overnight and in rain, to keep the duty cycle high, and avoid the quot drop sweep 
quot mode.


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Jordan Goodman Review of Plans Budgets
phototube budget how many do we have total when everything is done?
  To date 
    450 full price tubes
    116 half price tubes
  To be ordered 
    350 paid for
  Total 
    916 total
  Lost 
    20 broken
     7 sold (will be bought again)
    10 in the pond are now dead, may be broken
    10 or so are missing, will probably be found
  Available 
    890 quot 20
  Design 
    450 air shower layer
    162 muon layer
    162 or 200 in hadron layer if these tubes are centered above the muon tubes
    190 or 228 if these tubes are at the corners (below the air shower layer)
  Total goes from 774 to 840 
  Available for outriggers 50 120 tubes we also have ~30 Burle tubes that can be 
used for these


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Stefan Westerhoff et al. Discussion on Monte Carlo Simulations 
  will probably get together as a smaller group to decide where this is going
Gaurang 
  has document of real cosmic ray fluxes
    Parente et al Astroparticle Physics 1995, 3, 17
    compilation of various data
      protons 1.73e4 e^ 1.81
      for E_ 100 GeV, flux is 5.14 m^ 2 sr^ 1 s^ 1
      above 1 TeV 0.89
  shows simulation starting at 100 GeV, 80 tube threshold, varying attenuation 
length in the water at attenuation of 6m, get 350 Hz, at 4m get 275 Hz
    thus our trigger rate is a sensitive measurement of the attenuation length 
Mei Li Chen
  UMd ++ (+Berley + Ellsworth)
  using EAShower + Milagrosim
Stefan
  using CORSIKA + GEANT
  make working group on Monte Carlo anyone who wants is welcome


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Discussion on Analysis Data Taking Strategy
Are we ready to sacrifice some virgins?
Finish calibration first!
Candidates Moon, Mrk 501 (Stefan NO!), Crab, Mrk 421, Y 
other possibilities multiplicity single muons use to predict what we're gonna see 
Need a plan first 

Need to learn how to reconstruct first How can we make an 
energy cut for sure then we would be able to do the Moon Look 
at large showers, small zenith angles Some arguments for using 
the Crab as a standard candle gammas rather than just protons 
go ahead and sacrifice? Agreed that this discussion can be 
tabled at least until the next collaboration meeting while we 
understand all the things that hinder our reconstruction 
slewing, curvature, etc



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