IceCube Institutional Memorandum Of Uderstanding (MOU)

LBNL is involved in many aspects of IceCube service. We built the DOM main boards, and many of our service tasks are related to that, including maintenance of DAQ hardware (contributing to firmware and online software updates). Over the past year, PI Klein has gotten in the PINGU coordination committee, and the Gen2 HEA/Surface working group, where he is looking into complete event reconstruction for high-energy (i. e. TeV+) events containing a cascade plus a muon, and also looking at ‘forward muon’ events where a muon takes a large fraction of the air shower energy; this is an important background for downward-going neutrino events.

We are also heavily involved in software work. LBNL’s NERSC is responsible for storing a copy of all of IceCube’s raw data on their HPSS storage system. The MOU envisions us storing 3.3 petabytes the end of the first year, increasing by about 700 terabytes/year. This is a lot of data, and we have been heavily involved in developing the data transfer procedures. We also have an allocation of 1,000,000 CPU hours this year on NERSC supercomputer systems, and have been expending considerable effort to make IceCube software work on this or similar systems. IceProd, in particular, does not easily run here. We are fortunate in that former IceCube postdoc, now NERSC staffer Lisa Gerhardt is able to take some time to help us with these projects.

Postdoc Tomasz Palczewski is our group “PI” for our computing efforts at NERSC, works on NERSC software issues, and has also taken responsibility for a number of IceCube modules.

We continue to maintain our original responsibilities, including the maintenance and upgrading (including ‘restandardization’) for the truncated mean muon energy measurement. Gary Binder has been looking into an improved maximum likelihood method to further improve TM.

Our analysis efforts are focused in several areas.

The first is a search for extraterrestrial neutrinos, especially cascades, where we have multiple efforts covering different energy ranges. Gary Binder made the first analysis of the flavor content of astrophysical neutrinos. He is now finishing up a measurement of inelasticity (muon energy/neutrino energy) in contained events; this can be used to determine the neutrino/antineutrino ratio (at energies below about 40 TeV), and also to search for  _ . This has necessitated developing new reconstruction algorithms to determine the cascade and muon energy in these more complex events.

Palczewski is working on a study of high-energy down-going neutrinos. He is applying algorithms to select single muon events (developed for the forward muon search) to reject muon bundle background.

Finally, Miarecki is working on a paper on her thesis topic: a measurement of the neutrino-nucleon cross-section by measuring atmospheric neutrino absorption in the Earth.

We use the National Energy Research Supercomputer Center (NERSC) to produce Monte Carlo event samples; this has mostly been cascade signal events. T. Palczewski maintains the software installation and coordinates this production. For CY 2017, we have an allocation of 1,000,000 CPU hours on Cori Phase 1 ( http://www.nersc.gov/systems/cori/ ), which uses 2.3 GHz Intel Haswell processors. Averaged over 365 days running 24/7, this is equivalent to 114 full-time processors. We have also been allocated enough tape and disk storage to story a complete copy of the IceCube raw data. We anticipate using the CPU time mostly for IceCube, but this is negotiable.

Labor Cat.	Names	WBS L3	Tasks	Funds Source	WBS 2.1	WBS 2.2	WBS 2.3	WBS 2.4	WBS 2.5	WBS 2.6	Grand Total
					Program Coordination	Detector Maintenance & Operations	Computing & Data Management	Data Processing & Simulation	Software	Calibration
KE	KLEIN, SPENCER	Administration	Supervise LBNL effort	NSF M&O Core	0.05						0.05
		Computing & Data Management	Oversee raw data storage at LBNL	Institutional In-Kind			0.08				0.08
		Administration	PINGU Coordination Committee	Institutional In-Kind	0.03						0.03
		Administration	Gen2 HEA/Surface working group	Institutional In-Kind	0.05						0.05
	KLEIN, SPENCER Total				0.13		0.08				0.21
PO	PALCZEWSKI, TOMASZ	Detector Monitoring	Monitoring Shifts	Base Grant		0.09					0.09
	PALCZEWSKI, TOMASZ Total					0.09					0.09
EN	STEZELBERGER, THORSTEN	Data Acquisition	Maintain DAQ Hardware	NSF M&O Core		0.15					0.15
	STEZELBERGER, THORSTEN Total					0.15					0.15
GR	BINDER, GARY	Reconstruction	High-energy combined event reconstruction	Base Grant					0.15		0.15
	BINDER, GARY Total								0.15		0.15
IT	All, LBNL IT	Central Computing Resources	NERSC Data Archiving, Distributed Computing and Labor	Institutional In-Kind			1.00				1.00
	LBNL IT Total						1.00				1.00
	LBNL Total				0.13	0.24	1.08		0.15		1.60