Hey guys, feel free to add, edit, organize in a way that would make the most sense for someone new to the group. There may be mistakes, unfinished definitions, irrelevant definitions, duplicate definitions, etc. as this document is under construction. If you have any comments or suggestions, please contact Carter Eikenbary.

Since this doc covers a lot, try using ctrl+F (or command+F on Macs) to find things.

Could use input from some hardware people in particular.

See also:

the CDMS recommended-reading list on Confluence for links to more in-depth information

        The Standard Figures Confluence page : helpful figures for explaining various aspects of the experiment

General Stuff

Physics

WIMP - Weakly Interacting Massive Particle

        Note that we are specifically looking for WIMPs that weigh less than 10 Gev/c2

FCP - Fractionally-charged Particle

LIP - Lightly Ionizing Particle; free FCPs

LDM - light dark matter

ALP - Axion-like particle

BSM - beyond standard model

CMB - Cosmic microwave background

SHM - ‘standard halo model’:

isotropic (i.e. symmetric), isothermal (same-temperature), nonrotating sphere of dark matter around galaxy

        (individual dark matter particles have velocity, but the overall distribution doesn’t change)

LSR - ‘local standard of rest’

The Galactic LSR is the average orbital circular velocity at the Sun’s distance from the galaxy’s center

Neganov-Trofimov-Luke (NTL) effect - in our case, electrons and holes drift through our detector volumes

due to the applied electric fields; they reach a sort of terminal velocity due to interactions with the

surrounding lattice atoms, and further work applied causes them to emit ‘NTL’ phonons.

Phonons - vibrations that propagate through a lattice like particles

NTL/Luke phonons - phonons emitted when charges in an applied field exceed their max drift speed

        (emitted in a sort of cone around the direction the charge propagates)

Prompt phonons - emitted directly in interactions with nuclei

        (emitted isotropically)

NR, ER - nuclear recoils, electron recoils

Ionization yield - ratio of charge signal to recoil energy. (We use it to help distinguish between NRs and ERs)

Bandgap - energy needed to liberate an electron (i.e. move it from valence band to conduction band)

PDF - probability distribution function

CDF - cumulative distribution function (basically the integral of a PDF)

SD, SI - spin-dependent, spin-independent

Inelastic scattering: two particles interact; three (or more) particles leave

Bremsstrahlung - ‘Breaking radiation’: A particle emits radiation as it slows down--e.g. due to another particle.

Migdal effect - After DM collision, a nucleus is slightly ionized as its electron cloud tries to catch up

Places/Groups you should know:

hepx - high energy physics experiment - includes CMS, CDMS, CDF, astronomers, phenomenologists

CMS - Compact Muon Solenoid (Experiment), a particle physics detector at CERN

(CMS 45,000-person collaboration, CDMS 150 person collaboration ?)

CDF - Collider Detector at Fermilab - Proton Antiproton Collider (Dave’s previous experiment)

SUF - Stanford Underground Facility - group of 3 computers (“Titus”,”Nero”, and “Galba”) in California that the

CDMS collaboration uses for various purposes - holds documentation for CDMS and the CDMS-developed

code (git repositories) - mostly for CDMS 2 (Soudan)

SLAC - SLAC National Accelerator Laboratory - formerly the Stanford Linear Accelerator Center

FNAL - Fermilab National Accelerator Lab

Soudan - a mine in Minnesota. Some previous experiments done there.

SNOLAB - a facility in Vale Inco Mine in Sudbury, Canada, where our next experiment will be.

Our Experiment

CDMS - Cryogenic Dark Matter Search (collaboration). Name has evolved with experiment over time:

        -CDMS I was run at Stanford University (1998-2002) (‘shallow site’ in some older papers…)

        -CDMS II was run in the Soudan mine in Minnesota (2003-2009) (‘deep site’...)

        -SuperCDMS (Soudan) was also run at the Soudan mine, but with better equipment. (2011-2015)

        -SuperCDMS (SNOLAB), the next experiment, will be run in Canada. (2022? - ?)

CDMSlite - low ionization threshold experiment - lowers the energy threshold by applying higher ‘bias’ voltage across detectors.

        Uses the NTL effect to essentially turn ER energies into larger NR energies

        So the phonon sensors are now good ionization sensors, but we can’t distinguish between ERs and NRs

CDMSbats - (disambiguation) This is a particular software package, NOT a kind of experiment. Read more below.

‘The Project’ - refers to building of superCDMS

We are specifically looking for dark matter with mass below 10 Gev/c2

Experiment specifics

different types of detectors/modes on CDMS:

        -some detectors are made of germanium, others of silicon

-IZIP - Interleaved Z-sensitive Ionization and Phonon [detector]

-CDMSlite mode - higher bias voltage applied over detector

-HV detector - optimized for phonon sensitivity, no charge collection

-mZIP - optimized for phonon sensitivity, includes charge collection

Parts of the detectors:

FET - field-effect transistor. Used to pick out charges

TES - transition-edge sensor. Used to pick out phonons

        Both of the above translate into a change in electrical current in the experiment.

        channels - segments of the detector dedicated to phonon or charge signals

SQUID - superconducting quantum interface device; measured/amplified TES current change (outputs our ‘phonon pulse’)

DIB - Detector Interface Board (each Soudan iZIP had 2, one per side [I think])

RTF - Receiver trigger filter (board); where trigger energy thresholds are set (each Soudan iZIP had 2, one per side [I think])

        DIB -> RTF -> Trigger logic board

Veto - Scintillators surrounding the entire apparatus--outside the shielding.

If we see an event here, we ignore it in the data--it’s outside interference.

(WIMPS would come from outside, but they aren’t likely to interact more than once)

QET - quasiparticle assisted, electrothermal feedback, TES

fiducial - reliable, trustworthy, etc. The ‘fiducial region’ of a detector is where reliable data comes from.

        -i.e. Not near the edge, away from potential interference

tower - i.e. ‘detector tower’, i.e. detectors stacked on top of one another

        The Soudan experiments, for example, consisted of five towers of 3 detectors each.

          Each detector was specified by tower and position in the tower as T#Z#:

                T1Z1 = tower 1, zip 1 (the top detector of the ‘first’ tower)

                T4Z2 = tower 4, zip 2 (the middle detector of the ‘fourth’ tower)

                T5Z3 = tower 5, zip 3 (the bottom detector of the ‘last’ tower)    (etc…)

Cryostat - cold stuff! Set of cans inside the shielding connected to an external fridge. Detectors inside.

Shielding:

        Ancient lead: old lead in which all the radioactive stuff has decayed away. Small layer at Soudan.

        (new) lead: Still has some radioactivity, but can block outside stuff. Larger layer outside the ancient lead at Soudan.

        Polyethylene: inside and outside the lead shielding layers. Catches lots of neutrons?

Calibration sources - radioactive sources introduced to the experiment so we can calibrate energies

E.g. Ba-133 for photons, Cf-252 for neutrons

Contaminants - elements that will show up in data since we can’t get rid of them

        radon/polonium/bismuth/lead decay chain, activated germanium

CStem, EStem or Cryo, Vacuum- terms referring to the tubes where the cryogenics and electronics entered the detector

        The electronics stem leads out to the DAQ.

        Calibration sources could be placed inside these tubes.

Organization

WBS - work breakdown structure - the breakdown of what needs to be done for the experiment, and in what order, estimating costs of everything, etc. (i.e. this is more logistics than physics)

e.g. WBS 1.6.4 refers to the monitoring system for CDMS

1.5 - building the electronics (DCRC, the trigger board detector control and readout card)

1.6 - trigger in DAQ - Data acquisition system

1.8 - computing and software

P6 - name of the program that we enter all of the information for the WBS

TDR - technical design report, describes the outline of the experiment that you're making in an attempt to get money

Hardware

Message Passing Interface (MPI) - used for parallel processing. An mpi job requests multiple cores and then data is passed from one core to another in real time.

-Running multiple jobs, it's a way to pass information between multiple computers

Rev G - Rev is short for revision, revisions for DCRC (D0/D.0 and D1 are also abbreviations, from Rev C to Rev G)

DCRC - Detector Control and Readout Card - power source and the readout system for the detector

SN - Naming convention used to identify DCRC boards (SN50).

CIC Filter - Cascaded Integrator Comb - A way of reducing the sampling rate of data without increasing noise

FIR - Finite impulse response - type of digital filter, allows you to control for different variables, (for trigger)

MiniBOB (Mini Break Out Board) - breaks little pin connectors on circuit boards into larger connectors

Trigger Simulations (aka TriggerSim, TrigSim) - a program used to simulate triggered events

linear search module, peak search module - modules for the trigger, that do slightly different things

ADC -analogue-to-digital converter

test bench -

DAQ - Data acquisition (system)

MIDAS (Maximum Integrated Data Acquisition System) - developed at PSI and TRIUMF (written in C++)

trigger firmware -

level 1 trigger (energy pulse)

FPGA -  field programmable GPA: computer/chip without an operating system so it runs 1 task really fast

(and can run modules in parallel!!) Write firmware on this, not software (?)

firmware: 'software' without an operating system.

Altara chip, programming in VHCL

    timing simulation module

    propagation delay - how long it takes to get through all your computing before looking at the output/switching delays -

    register - memory location on the chip

    duty cycle - what fraction of the time you're working on something. The breakdown of how much time you spend on what task

finite impluse response (FIR) - digital processing tool that can be used to make a filter

THL selector - threshold logic selector - 8 submodules

ODB - online database

KVM - keyboard video monitor it's a setup where you have one keyboard/monitor setup between multiple computers

Prebias - hold detectors at a voltage higher than the operating voltage and reduce back to normal to take data

        This is done to release trapped charges beforehand to reduce noise.

Software

GitBlit - where the collaboration stores all its git repositories (several of the following are in GitBlit)

GitLab - replacement for GitBlit

SimWorkFlowTools (SWFT): Repository containing scripts to guide a user through the full sample production chain (sourcesim, DMC, DAQSim, and cdmsbats). The plan is for it all to be automated some day.

SuperSim - Code handling the first stage of our simulations, one way or another. Models incoming particles and/or detectors.

-- what you call the montecarlo of the source -- simulation of particle with the detector with physics parameters

-- outputs of supersim go into DMC or it can do the DMC itself (G4DMC)

-- ‘SuperSim samples’: the elements we simulate: Ba-133, Cf-252, Ge-71, etc.

SimProdMacros - Repository that contains all of the SuperSim (Geant4) macros necessary to

generate the major background and signal sources produced for the SuperCDMS

experiment.

WIMSim - auxiliary program for simulating WIMPS in SuperSim

DMC - Detector Monte Carlo

DMC picks up how the detector responds to the supersim file/output

Geant4 - GEometry And Tracking (4): A physics library from CERN. Used by SuperSim.

G4CMP - Geant4-based condensed matter physics. Tells the G4DMC how to do solid-state stuff.

G4DMC- SuperSim also modeling the detector response

        (compare MatlabDMC, which models the detector separately, outside SuperSim)

CrystalSim - detector response simulation (i.e. what the detector itself does when a source particle has hit it)

FETSim, TESSim - readout pulse simulations

TES_ODE - Transition Edge Sensor program; repository in GitBlit

WIMP50 Samples- Simulated WIMPs (see above) with energy of 50 GeV

preproduction/DMCPreBats/DAQSim - take the DMC (i.e. simulation) results and scale, format, and possibly add noise so that it can be processed by CDMSbats as if it were real data.

IOWriter - IOWriter is part of the IOLibrary that writes events in midasIO format.

Midas IOWriter (in DAQSim) - Integrating standard CDMS I/O functions from the IOLibrary repository into DAQSim

CDMSbats - production package from CDMS. We use it in our simulations, but it is also what gets used in the real experiment.

        -’reconstruction’

Soudan-format binary writer - writes out data in the same format as was used in the Soudan experiment

PSD - Power Spectrum Density - A way to characterize noise as a function of frequency (Fourier transforms)

Macro - a more general computing concept, but most often here it means a file that tells SuperSim/Geant4 what to do.

Production Dataset - CDMS datasets that have been run through the full SourceSim/DetectorSim/CDMSBats production chain.

DataCatalog - Stores metadata for each simulation dataset. Specifically, the link (storage site and file path)  to the dataset and information about the dataset.

ReleaseBuilder - Software to automatically check out specific tags of all packages needed for SuperCDMS simulation, reconstruction, and analysis, build them, and generate a script (env.sh) to configure the user's environment appropriately for all of them.

Production consists of:

    -Simulation

        -SourceSim

            -SuperSim (G4DMC could start here also)

              -event generation - SuperSim modeling incoming particles moving into experiment volumes

            -Optional postprocessing

        -DetectorSim

            -DMC

              -G4DMC or MatlabDMC (these are two different sets of code! Use either one or the other.)

                -CrystalSim or FETSim/TESSim

            -DAQSim - puts simulation output into format like real data so it can be put into the actual analysis code

    -Reconstruction

Analysis

Et - total phonon energy.  Et = Er + ENTL        (units of keVt)

        Er - sum of primary and relaxation phonon energy

        ENTL - sum of NTL phonon energy

Er,ee - electron equivalent energy, ; that is, the energy assuming all recoils are electron recoils (ionization yield = 1) (units of eVee)

Er,nr - nuclear recoil equivalent energy, which is some complicated calibration of the electron equivalent energy (units of eVnr)

(1 keVt ~ 66 eVee ?)

Lindhard yield model - provides yield as a function of nuclear recoil energy (involved in Er,ee to Er,nr calibration)

Signal trace - The data, basically. Modeled as a scalable template plus some Guassian noise (for CDMSlite, at least)

(This old CDMSWiki page has a more complete list of some of the things below)

RQ - ‘reduced quantity’ : raw traces are converted (‘reduced’) by the DAQ into useful quantities

RRQ - ‘refined reduced quantity’ : rqs that have been processed a little more

        E.g.: the optimal filter amplitude in volts is an rq

But the optimal filter measured energy in keV, which has been through calibration, is an rrq

Signal analysis algorithms:

    OF - (standard) optimal filter. Good for position measurements, bad for energy measurements

    NSOF - nonstationary optimal filter. Bad for position measurements, good for energy measurements.

    2T - 2-template algorithm. Other two algorithms just used one template; this one combines a ‘slow’ and ‘fast’ template.

        The ‘slow’ template is the one used by the OF and NSOF. The ‘fast’ template is based on differences between the

          slow template and the traces used to construct it (‘residual traces’).

        Good for both energy and position?

PTNF (Phonon Total Nonstationary Filter) - a measure of the total energy deposited in the detector through phonon channels

ytOF (Yield Total; Optimal Filter) - (see ‘ionization yield) qsummaxOF/precoiltOF  *definition might depend on which analysis

ytNF (Yield Total; Nonstationary Filter) - qsummaxOF/precoiltNF   *definition might depend on which analysis

AFB - Forward Backward Asymmetry: (#forward - #backward)/total

SNR - signal-to-noise ratio

Computing

CVMFS - Cern Virtual Machine File System - The file system for the virtual machines at cern, and elsewhere

SLAC account - provides access to Confluence

Confluence - webpages with documentation for CDMS, mostly CDMS 3 (Snolab)

HPRC: High Performance Research Computing. TAMU’s campus-wide computing cluster.

        Includes machines Ada, Terra, and Curie.

Brazos Cluster: DEPRECATED TAMU computer cluster that our group monitors

--’stakeholder’: partition/group of computing nodes into which lots of people have invested money.

So it’s fast, but the people with money have priority for their jobs. Mitchell institute

--’background’: more general partition/group of computing nodes

    PHEDEX - physics experiment data export - automated way of getting data

    PHEDEX transfers

    CMSSW - CMS experiment SoftWare (runs in crab jobs, it's how you package the data for that particular experiment)

    SAM test - site availability monitor - the name of CERNS monitoring system

    Condor - is the scheduler for the local grid endpoint science cluster -   our local is slurm

    SAM - site availability monitor - the name of CERNS monitoring system

    CATS Tests - CRAB (CMS remote analysis builder) automated test submission

- dummy tests to make sure that CERN jobs are working.

    SLURM - job submission system on Brazos [What is slurm][slurm instruction in Brazos webpage]

ROOT- Data Analysis Framework - C++ library developed by CERN

Crontab - A program that runs other programs on a schedule

ROOTANA- ROOT based system for MIDAS - interface package for ROOT and MIDAS

Qubit- Most basic unit of information in quantum computing (Quantum Bit)

Other/New Stuff that hasn’t been organized yet!

Useful quantities:

    (These taken from CDMSlite paper. The uncertainties can have significant effects.)

    Local dark matter mass density: ⍴0 = 0.3 GeV/(c2 cm3) [relevant xkcd]

    Galactic LSR: 𝚯0 = 220±20 km/s

    Galactic escape velocity: 544+64-46 km/s

    Solar peculiar velocity w/ respect to other stars: (11±1.2, 12.24±2.1, 7.25±1.1) km/s

        that is, (radial, tangential, vertical) velocity in the galaxy

Zoom - program we/CDMS use(s) for meetings

ENSDF, EADL, ENDF, XDB… : some databases/references that may be referred-to in our work.

Many are linked from the National Nuclear Data Center, which also has a nice chart of nuclides

Slac Collaboration

ETV

daq group

'DU time' exceed the limit - a Brazos monitoring error; ‘DU’ is a shell command that checks disk usage.

303 vs 291 mismatch

cluster heartbeat

data processing - going from 500 to 3000 - some jobs have a memory management where they're trying to access all

LEN

Low Threshold

slac computing account

bbar - b particle experiments

tier 2s: PNNL pacific north west national lab, and TAMU

spitzer

modified newtonian dynamics observational paper (MOND)

madGraph - program for collider physics

susy search - supersymmetry

l-gaps, comity buzz word

shortlisted

veto-factor?

optimal interval method

snolab high voltage detector

OSG-

SDU model

Ctrl-F disambiguation for typos:

Searched for this:                                Probably looking for this: