bluuebunny/crossref_metadata_2025 huggingface dataset:
Emerging paper microfluidic devices
Authors: Gao Bingbing , Li Xin , Yang Yaqiong , Chu Jianlin , He Bingfang
Published: September 2019

Paper has unique advantages over other materials, including low cost, flexibility, porosity, and self-driven liquid pumping, thus making it widely used in various fields in biology, chemistry, physics and materials science.
Surface functionalization of polyoxovanadium clusters: generation of highly soluble charge carriers for nonaqueous energy storage
Authors: VanGelder Lauren E. , Pratt Harry D. , Anderson Travis M. , Matson Ellen M.
Published: September 2019

Here, we demonstrate the effects of surface functionalization on a tunable series of nano-sized electron shuttles toward improving their function in nonaqueous energy storage.
Total synthesis of verucopeptin, an inhibitor of hypoxia-inducible factor 1 (HIF-1)
Authors: Takahashi Nobuaki , Hayashi Hideaki , Poznaks Viktors , Kakeya Hideaki
Published: September 2019

The first total synthesis of vercopeptin (1), an inhibitor of hypoxia-inducible factor 1 (HIF-1), was achieved via condensation of the depsipeptide core and the polyketide side chain unit.
A bioinspired, photostable UV-filter that protects mammalian cells against UV-induced cellular damage
Authors: Martin Camille A. , Rezaeeyazdi Mahboobeh , Colombani Thibault , Dinneen Sean R. , Kumar Amrita , Bencherif Sidi A. , Deravi Leila F.
Published: September 2019

We demonstrate the application of xanthommatin (Xa), a biochrome present in arthropods and cephalopods, as an alternative chemical UV-filter that is cytocompatible while maintaining photostability and photoprotective properties.
A tetraphenylethylene-based covalent organic polymer for highly selective and sensitive detection of Fe3+ and as a white light emitting diode
Authors: Zhang Han , Zhou Jie , Shan Guo-Gang , Li Guang-Fu , Sun Chun-Yi , Cui Dong-Xu , Wang Xin-Long , Su Zhong-Min
Published: September 2019

A new COP is synthesized, exhibiting excellent performance as an Fe3+ sensor with a LOD of 23.5 ppb, and solid-state illumination.
Enhancement of the crystallization and biocompatibility of poly(TMC-b-(LLA-ran-GA)) by poly(lactide) stereocomplex
Authors: Fan Tiantang , Qin Jingwen , Lin Shengli , Ye Wuyou , Li Jiafeng , Zhang Qin , Gong Li , Liu Dongyang , Fan Zhongyong
Published: September 2019

A series of poly(1,3-trimethylene carbonate-b-(l-lactide-ran-glycolide)) (PTLG) with the three-armed PDLA and PLLA stereoblock copolymer (sc-PLA) acting as the nucleating agent was preparedviathe solution-casting method.
Understanding the selectivity of inhibitors toward PI4KIIIα and PI4KIIIβ based molecular modeling
Authors: Tian Shuaizhen , Zeng Jinzhe , Liu Xiao , Chen Jianzhong , Zhang John Z. H. , Zhu Tong
Published: September 2019

Molecular dynamics simulations and binding free energy calculations are combined to investigate the selectivity of inhibitors toward type III phosphatidylinositol 4 kinases.
A reaction density functional theory study of the solvent effect in prototype SN2 reactions in aqueous solution
Authors: Cai Cheng , Tang Weiqiang , Qiao Chongzhi , Jiang Peng , Lu Changjie , Zhao Shuangliang , Liu Honglai
Published: September 2019

Reaction density functional theory (RxDFT), combining quantum DFT with classical DFT, has been employed to investigate the solvent effect and free energy profiles of SN2 reactions in aqueous solution.
The ionization energy of the vinyl radical: a Mexican standoff with a happy ending
Authors: Wu Xiangkun , Zhou Xiaoguo , Hemberger Patrick , Bodi Andras
Published: September 2019

Theoretical approaches and experimental spectra are confirmed as the origin transition is shown to be forbidden in vinyl photoionization.
Enhancement of electron accepting ability of para-benzoquinone by a single water molecule
Authors: Mensa-Bonsu Golda , Lietard Aude , Verlet Jan R. R.
Published: September 2019

Electron acceptors built upon the para-benzoquinone (pBQ) electro-phore are ubiquitous in nature.
Structure, electrical conductivity and oxygen transport properties of perovskite-type oxides CaMn1−x−yTixFeyO3−δ
Authors: Ruhl Rian , Song Jia , Thoréton Vincent , Singh Sathya Prakash , Wiik Kjell , Larring Yngve , Bouwmeester Henny J. M.
Published: September 2019

Correlating ionic and electronic transport properties with structural changes in perovskite-type oxides CaMn1−x−yTixFeyO3−δ (CMTF).
Correction: Surface heterogeneity and inhomogeneous broadening of vibrational line profiles
Authors: Taj Skandar , Baird Diane , Rosu-Finsen Alexander , McCoustra Martin R. S.
Published: September 2019

Correction for ‘Surface heterogeneity and inhomogeneous broadening of vibrational line profiles’ by Skandar Taj et al., Phys. Chem. Chem. Phys., 2017, 19, 7990–7995.
Half adder and half subtractor logic gates based on nicking enzymes
Authors: Zhao Yunbin , Liu Yuan , Zheng Xuedong , Wang Bin , Lv Hui , Zhou Shihua , Zhang Qiang , Wei Xiaopeng
Published: September 2019

A series of DNA logic devices with simple structure and extremely short reaction time.
Correction: One-pot synthesis of a new generation of hybrid bisphosphonate polyoxometalate gold nanoparticles as antibiofilm agents
Authors: Tomane S. , López-Maya E. , Boujday S. , Humblot V. , Marrot J. , Rabasso N. , Castells-Gil J. , Sicard C. , Dolbecq A. , Mialane P. , Vallée A.
Published: September 2019

Correction for ‘One-pot synthesis of a new generation of hybrid bisphosphonate polyoxometalate gold nanoparticles as antibiofilm agents’ by S. Tomane et al., Nanoscale Adv., 2019, 1, 3400–3405.
Physicochemical exfoliation of graphene sheets using graphitic carbon nitride
Authors: Priyanka V. , Savithiri G. , Subadevi R. , Suryanarayanan V. , Sivakumar M.
Published: September 2019

The development of methods for the synthesis of graphene on a large scale at an affordable cost using less toxic materials has attracted significant interest in recent years.
Hollow cobalt sulfide for highly efficient uranium adsorption from aqueous solutions
Authors: Dou Weixin , Yang Weiting , Zhao Xiaojun , Pan Qinhe
Published: September 2019

The preparation of hollow Co3S4nanostructures by ZIF-67 guarantees high uranium adsorption performance in aqueous solutions.
Smart supramolecular gels of enolizable amphiphilic glycosylfuran
Authors: Thamizhanban Ayyapillai , Lalitha Krishnamoorthy , Sarvepalli Guru Prasanth , Maheswari C. Uma , Sridharan Vellaisamy , Rayappan John Bosco Balaguru , Nagarajan Subbiah
Published: September 2019

In this report, bio-based amphiphilic glycosylfurans were synthesized using a biocatalyst. For the first time, we are reporting on hydrogelation via in situ molecular tuning of amphiphilic glycosylfurans followed by a self-sorting mechanism.
A distorted lactam unit with intramolecular hydrogen bonds as the electron donor of polymer solar cells
Authors: Wang Hua-Chun , Ren Minrun , Cao Jian , Yin Hong-Bo , Zhang Guichuan , Xiao Jingyang , Ren Xiancheng , Yip Hin-Lap , Xu Yun-Xiang
Published: September 2019

The device based on PBDT-BTP-OD with IT-M exhibited power conversion efficiency of up to 9.54% thanks to the synergistic effect of the distorted lactam motif and side-chain engineering.
One-dimensional π–π stacking induces highly efficient pure organic room-temperature phosphorescence and ternary-emission single-molecule white light
Authors: Wen Yating , Liu Haichao , Zhang Shitong , Gao Yu , Yan Yan , Yang Bing
Published: September 2019

High-efficiency RTP of TX-Cl crystal was induced by one-dimensional π–π stacking, which significantly enhances both intersystem crossing (S1 → Tn) and radiative rate (T1 → S0). SMWLE was harvested by precisely controlling aggregating degree.
Period-luminosity diagram of long period variables in the Magellanic Clouds
Authors: Lebzelter T. , Trabucchi M. , Mowlavi N. , Wood P. R. , Marigo P. , Pastorelli G. , Lecoeur-Taïbi I.
Published: September 2019

Context. The period-luminosity diagram (PLD) has proven to be a powerful tool for studying populations of pulsating red giants. Gaia Data Release 2 (DR2) provides a large data set including many long-period variables (LPVs) on which this tool can be applied.

Aims. We investigate the location of LPVs from the Large and Small Magellanic Clouds in the PLD using various optical and infrared luminosity indicators from Gaia and 2MASS, respectively. We thereby distinguish between stars of different masses and surface chemistry.

Methods. The data set taken from the Gaia DR2 catalogue of LPVs allows for a homogeneous study from low- to high-mass LPVs. These sources are divided into sub-populations of asymptotic giant branch (AGB) stars according to their mass and their O- or C-rich nature using the Gaia-2MASS diagram developed by our group. This diagram uses a Wesenheit index WBP, RP based on Wesenheit functions in the Gaia and 2MASS photometric bands. Four different luminosity indicators are used to study the period-luminosity (P–L) relations.

Results. We provide the first observational evidence of a P–L relation offset for both fundamental and 1O pulsators between low- and intermediate-mass O-rich stars, in agreement with published pulsation predictions. Among the luminosity indicators explored, sequence C′ is the narrowest in the P–WBP, RP diagram, and is thus to be preferred over the other PLDs for the determination of distances using LPVs. The majority of massive AGB stars and red supergiants form a smooth extension of sequence C of low- and intermediate-mass AGB stars in the P–WBP, RP diagram, suggesting that they pulsate in the fundamental mode. All results are similar in the two Magellanic Clouds.
Protostellar Outflows at the EarliesT Stages (POETS)
Authors: Moscadelli L. , Sanna A. , Goddi C. , Krishnan V. , Massi F. , Bacciotti F.
Published: September 2019

Context. Although recent observations and theoretical simulations have pointed out that accretion disks and jets can be essential for the formation of stars with a mass of up to at least 20 M⊙, the processes regulating mass accretion and ejection are still uncertain.

Aims. The goal of the Protostellar Outflows at the EarliesT Stages (POETS) survey is to image the disk-outflow interface on scales of 10–100 au in a statistically significant sample (36) of luminous young stellar objects (YSO), targeting both the molecular and ionized components of the outflows.

Methods. The outflow kinematics is studied at milliarcsecond scales through very long baseline interferometry (VLBI) observations of the 22 GHz water masers, which are ideal test particles to measure the three-dimensional (3D) motion of shocks owing to the interaction of winds and jets with ambient gas. We employed the Jansky Very Large Array (JVLA) at 6, 13, and 22 GHz in the A- and B-Array configurations to determine the spatial structure and the spectral index of the radio continuum emission, and address its nature.

Results. In about half of the targets, the water masers observed at separation ≤1000 au from the YSOs trace either or both of these kinematic structures: (1) a spatially elongated distribution oriented at close angle with the direction of collimation of the maser proper motions (PM), and (2) a linear local standard of rest (LSR) velocity (VLSR) gradient across the YSO position. The kinematic structure (1) is readily interpreted in terms of a protostellar jet, as confirmed in some targets via the comparison with independent observations of the YSO jets, in thermal (continuum and line) emissions, reported in the literature. The kinematic structure (2) is interpreted in terms of a disk-wind (DW) seen almost edge-on on the basis of several pieces of evidence: first, it is invariably directed perpendicular to the YSO jet; second, it agrees in orientation and polarity with the VLSR gradient in thermal emissions (when reported in the literature) identifying the YSO disk at scales of ≤1000 au; third, the PMs of the masers delineating the VLSR gradients hint at flow motions at a speed of 10–20 km s−1 directed at large angles with the disk midplane. In the remaining targets, the maser PMs are not collimated but rather tend to align along two almost perpendicular directions. To explain this peculiar PM distribution, and in light of the observational bias strongly favoring masers moving close to the plane of sky, we propose that, in these sources, the maser emission could originate in DW-jet systems slightly inclined (≤30°) with respect to edge-on. Magneto-centrifugally driven DWs could in general account for the observed velocity patterns of water masers.
The ATLAS Access Manager Policy Browser: state-of-the-art web technologies for a rich and interactive data visualization experience
Authors: Soloviev Igor , Avolio Giuseppe , Perrin Sami
Published: September 2019

The ATLAS experiment is operated daily by many users and experts working concurrently on several aspects of the detector. The safe and optimal access to the various software and hardware resources of the experiment is guaranteed by a role-based access control system (RBAC) provided by the ATLAS Trigger and Data Acquisition (TDAQ) system. The roles are defined by an inheritance hierarchy. Depending on duties, every ATLAS user has a well-defined set of access privileges (rules) corresponding to a specific set of assigned roles. In total, there are several hundred roles and several thousand users. Over the years, the system grew up in terms of users and roles, motivating the deployment of a visualization tool named “Policy Browser”. Currently, it is the primary tool for role administrators to manage all the aspects of the Access Management via a rich web-based interface. This paper presents the requirements, design and implementation of the “Policy Browser”. The tool is able to aggregate and correlate all the information provided by the RBAC system and offers a visual representation of the interrelations occurring among roles, users, hosts and rules. Additionally, the “Policy Browser” implements a powerful and flexible query mechanism facilitating the browsing of all the authorizations granted by the system. As an example of the available visual representations, the “Policy Browser” is capable of dynamically generating graphs to quickly display the role giving a user some defined privileges. A graph explorer is also provided in order to browse the role&s inheritance hierarchy. The “Policy Browser” is implemented using robust JavaScript frameworks: AngularJS, Bootstrap, D3.js for the front-end, and Django a python framework for the back-end. The use cases and the results based on an informal evaluation provided by the roles administrators are also presented.
An integrated system for data quality and conditions assessment for the ATLAS Tile Calorimeter
Authors: Smiesko Juraj
Published: September 2019

An integrated system for data quality and conditions assessment for the ATLAS Tile Calorimeter is known amongst the ATLAS Tile Calorimeter as the Tile-in-One. It is a platform for combining all of the ATLAS Tile Calorimeter offline data quality tools in one unified web interface. It achieves this by using simple main web server to serve as central hub and group of small web applications called plugins, which provide the data quality assessment tools. Every plugin runs in its own virtual machine in order to prevent interference between the plugins and also to increase stability of the platform.
Data Handling In The Alice O2 Event Processing
Authors: Richter Matthias , Krzewicki Mikolaj , Eulisse Giulio
Published: September 2019

The ALICE experiment at the Large Hadron Collider (LHC) at CERN is planned to be operated in a continuous data-taking mode in Run 3. This will allow to inspect data from all Pb-Pb collisions at a rate of 50 kHz, giving access to rare physics signals embedded in a large background.

Based on experience with real-time reconstruction of particle trajectories and event properties in the ALICE High Level Trigger, the ALICE O2 facility is currently designed and developed to support processing of a continuous, triggerless stream of data segmented into entities referred to as timeframes.

Both raw data input into the ALICE O2 system and the actual processing of aggregated timeframes are distributed among multiple processes on a manynode cluster. Process communication is based on the asynchronous message
passing paradigm.

This paper presents the basic concept for identification of data in the distributed system together with prototype implementations and performance measurements.
Readout Software for the Alice Integrated Online-Offline (O2) System
Authors: Chapeland Sylvain , Costa Filippo
Published: September 2019

ALICE (A Large Ion Collider Experiment) is a heavy -ion detector studying the physics of strongly interacting matter and the quarkgluon plasma at CERN’s LHC (Large Hadron Collider). During the second long shutdown of the LHC, the ALICE detector will be upgraded to cope with an interaction rate of 50 kHz in Pb–Pb collisions, producing in the online computing system (O2) a sustained input throughput of 3 TB/s. The readout software is in charge of the first step of data-acquisition, handling the data transferred from over 8000 detector links to PC memory by dedicated PCI boards, formatting and buffering incoming traffic until sent to the next components in the processing pipeline. On the 250 readout nodes where it runs, the software has to sustain a throughput which can locally exceed 100 Gb/s. We present the modular design used to cope with various data sources (hardware devices and software emulators), integrated with the central O2 components (logging, configuration, monitoring, data sampling, transport) and initiating the online data flow using the standard O2 messaging system. Performance considerations and measurements are also discussed.
Implementation Of The Atlas Trigger Within The Multithreaded Athenamt Framework
Authors: Stewart Martin—Haugh
Published: September 2019

We present an implementation of the ATLAS High Level Trigger (HLT) that provides parallel execution of trigger algorithms within the ATLAS multithreaded software framework, AthenaMT. This development will enable the HLT to meet future challenges from the evolution of computing hardware and upgrades of the Large Hadron Collider (LHC) and ATLAS Detector. During the LHC data-taking period starting in 2021, luminosity will reach up to three times the original design value. In the following data-taking period (2026) upgrades to the ATLAS trigger architecture will increase the HLT input rate by a factor of 4-10, while the luminosity will increase by a further factor of 2-3.

AthenaMT provides a uniform interface for offine and trigger algorithms, facilitating the use of offine code in the HLT. Trigger-specific optimizations provided by the framework include early event rejection and reconstruction within restricted geometrical regions. We report on the current status, including experience of migrating trigger selections to this new framework,and present the next steps towards a full implementation of the redesigned ATLAS trigger.
A Scalable Online Monitoring System Based on Elasticsearch for Distributed Data Acquisition in Cms
Authors: Andre Jean-Marc , Behrens Ulf , Branson James , Brummer Philipp , Chaze Olivier , Cittolin Sergio , Da Silva Gomes Diego , Darlea Georgiana-Lavinia , Deldicque Christian , Demiragli Zeynep , Dobson Marc , Doualot Nicolas , Erhan Samim , Jonathan Richard Fulcher , Gigi Dominique , Gladki Maciej , Glege Frank , Gomez-Ceballos Guillelmo , Hegeman Jeroen , Holzner Andre , Janulis Mindaugas , Lettrich Michael , Mecionis Audrius , Meijers Frans , Meschi Emilio , Mommsen Remigius K. , Morovic Srecko , O'Dell Vivian , Orsini Luciano , Papakrivopoulos Ioannis , Paus Christoph , Petrova Petia , Petrucci Andrea , Pieri Marco , Rabady Dinyar , Racz Attila , Rapsevicius Valdas , Reis Thomas , Sakulin Hannes , Schwick Christoph , Simelevicius Dainius , Stankevicius Mantas , Vazquez Velez Cristina , Vougioukas Michail , Wernet Christian , Zejdl Petr
Published: September 2019

The part of the CMS Data Acquisition (DAQ) system responsible for data readout and event building is a complex network of interdependent distributed applications. To ensure successful data taking, these programs have to be constantly monitored in order to facilitate the timeliness of necessary corrections in case of any deviation from specified behaviour. A large number of diverse monitoring data samples are periodically collected from multiple sources across the network. Monitoring data are kept in memory for online operations and optionally stored on disk for post-mortem analysis. We present a generic, reusable solution based on an open source NoSQL database, Elasticsearch, which is fully compatible and non-intrusive with respect to the existing system. The motivation is to benefit from an offthe-shelf software to facilitate the development, maintenance and support efforts. Elasticsearch provides failover and data redundancy capabilities as well as a programming language independent JSON-over-HTTP interface. The possibility of horizontal scaling matches the requirements of a DAQ
monitoring system. The data load from all sources is balanced by redistribution over an Elasticsearch cluster that can be hosted on a computer cloud. In order to achieve the necessary robustness and to validate the scalability of the approach the above monitoring solution currently runs in parallel with an existing in-house developed DAQ monitoring system.
Data Preparation for NA62
Authors: Laycock Paul
Published: September 2019

In 2017, NA62 recorded over a petabyte of raw data, collecting around a billion events per day of running. Data are collected in bursts of 3-5 seconds, producing output files of a few gigabytes. A typical run, a sequence of bursts with the same detector configuration and similar experimental conditions, contains 1500 bursts and constitutes the basic unit for offline data processing. A sample of 100 random bursts is used to make timing calibrations of all detectors, after which every burst in the run is reconstructed. Finally the reconstructed events are filtered by physics channel with an average reduction factor of 20, and data quality metrics are calculated.

Initially a bespoke data processing solution was implemented using a simple finite state machine with limited production system functionality. In 2017, the ATLAS Tier-0 team offered the use of their production system, together with the necessary support. Data processing workflows were rewritten with better error-handling and I/O operations were minimised, the reconstruction software was improved and conditions data handling was changed to follow best practices suggested by the HEP Software Foundation conditions database working group. This contribution describes the experience gained in using these tools and methods for data-processing on a petabyte scale experiment.
A fully parametric option in the LHCb simulation framework
Authors: Siddi Benedetto Gianluca
Published: September 2019

Faster alternatives to a detailed, GEANT4-based simulation are being pursued within the LHCb experiment. In this context the integration of the Delphes toolkit in the LHCb simulation framework is intended to provide a fully parameterized option. Delphes is a modular software designed for general-purpose experiments such as ATLAS and CMS to quickly propagate stable particles using a parametric approach and to provide reconstructed physical objects as output. It includes propagation inside a magnetic field and parameterized response for tracking and muon systems as well as calorimeters. Particle energies are computed by smearing the initial visible particles momentaaccording to detector resolution. The present contribution illustrates the current status of the Delphes toolkit in Gauss, the LHCb simulation framework. In this integration the particle transport performed by GEANT4 and subsequent mimicking of detector response and reconstruction has been replaced with a parametric response of the various detector elements. The implementation required sig-nificant changes to Delphes itself to constrain the particle transport inside the detector acceptance and to match the LHCb dipole magnetic field. The configuration of various parametrisations of resolution and efficiency is also a major aspect of the work to provide a fully functional simulation. The output of the resulting fast simulation is formatted in such a way that can be used in the LHCb physics analysis framework.
A vectorization approach for multifaceted solids in VecGeom
Authors: Apostolakis John , Cosmo Gabriele , Gheata Andrei , Gheata Mihaela , Sehgal Raman , Wenzel Sandro
Published: September 2019

VecGeom [1] is a multi-purpose geometry library targeting the optimisation of the 3D-solids’ algorithms used extensively in particle transport and tracking applications. The implementations of these algorithms are templated on the input data type and are vectorised based on the VecCore [2] abstraction library in case of multiple inputs in a SIMD vector. This provides additional performance for applications supporting a multi-particle flow, such as the GeantV [3] prototype. VecGeom allows also scalar queries for all the supported solids, an option that started being used in Geant4 [4] since the release 10.2, as optional replacement of the geometry functionality provided by the native Geant4 solids. In single particle mode, VecGeom can still issue SIMD instructions by vectorizing the geometry algorithms featuring loops over internal data structures. This approach has proven to bring very large benefits for the tessellated solids represented in terms of triangular facets. To expose more vectorization in the scalar mode we have extended the approach used for the triangular tessellations to other multifaceted shapes, such as the extruded polygon, the poly-hedra and different trapezoids. We hereby present the strategy used to vectorise the different processing phases for tessellated solids, the performance improvements compared to the previous scalar implementations for other solids using this approach, and how this is reflected in Geant4 simulations using VecGeom as geometry engine.
Opticks : GPU Optical Photon Simulation for Particle Physics using NVIDIA® OptiXTM
Authors: Blyth Simon
Published: September 2019

Opticks is an open source project that integrates the NVIDIA OptiX GPU ray tracing engine with Geant4 toolkit based simulations. Massive parallelism brings drastic performance improvements with optical photon simulation speedup expected to exceed 1000 times Geant4 with workstation GPUs. Optical physics processes of scattering, absorption, scintillator reemission and boundary processes are implemented as CUDA OptiX programs based on the Geant4 implementations. Wavelength-dependent material and surface properties as well as inverse cumulative distribution functions for reemission are interleaved into GPU textures providing fast interpolated property lookup or wavelength generation. OptiX handles the creation and application of a choice of acceleration structures such as boundary volume hierarchies and the transparent use of multiple GPUs. A major recent advance is the implementation of GPU ray tracing of complex constructive solid geometry shapes, enabling automated translation of Geant4 geometries to the GPU without approximation. Using common initial photons and random number sequences allows the Opticks and Geant4 simulations to be run point-by-point aligned. Aligned running has reached near perfect equivalence with test geometries.
A scalable and asynchronous detector simulation system based on ALFA
Authors: Wenzel Sandro
Published: September 2019

In the context of the common online-offline computing infrastructure for Run3 (ALICE-O2), ALICE is reorganizing its detector simulation software to be based on FairRoot, offering a common toolkit to implement simulation based on the Virtual-Monte-Carlo (VMC) scheme. Recently, FairRoot has been augmented by ALFA, a software framework developed in collaboration between ALICE and FAIR, offering portable building blocks to construct message-based and loosely-coupled multiprocessing systems.

We will report here on the implementation of a scalable and asynchronous de-tector simulation system which is based on ALFA. The system offers paral-lelization at the primary-track level, going beyond the usual inter-event parallelism of Geant4-MT, and the possibility to asynchronously and simultaneously process simulation data for the purpose of digitization and clusterization. Core advantages of our implementation are an ideal reduction of the processing time per event as well as a reduction of the memory footprint, allowing us to make significantly better use of opportunistic resources, such as HPC backfills. Moreover, the track-level parallelism opens up the interesting possibility to use different simulation engines (such as Geant4 and Fluka) concurrently, based on simple selection filters on the primary particles. The integration of fast MC processes, such as machine learning kernels running on a dedicated GPU, are a natural extension to the system.
Generative Models for Fast Calorimeter Simulation: the LHCb case>
Authors: Chekalina Viktoria , Orlova Elena , Ratnikov Fedor , Ulyanov Dmitry , Ustyuzhanin Andrey , Zakharov Egor
Published: September 2019

Simulation is one of the key components in high energy physics. Historically it relies on the Monte Carlo methods which require a tremendous amount of computation resources. These methods may have difficulties with the expected High Luminosity Large Hadron Collider (HL-LHC) needs, so the experiments are in urgent need of new fast simulation techniques. We introduce a new Deep Learning framework based on Generative Adversarial Networks which can be faster than traditional simulation methods by 5 orders of magnitude with reasonable simulation accuracy. This approach will allow physicists to produce a sufficient amount of simulated data needed by the next HL-LHC experiments using limited computing resources.
New Developments in DD4hep
Authors: Petricˇ Marko , Frank Markus , Gaede Frank , Sailer André
Published: September 2019

For a successful experiment, it is of utmost importance to provide a consistent detector description. This is also the main motivation behind DD4hep, which addresses detector description in a broad sense including the geometry and the materials used in the device, and additional parameters describing, e.g., the detection techniques, constants required for alignment and calibration, description of the readout structures and conditions data. An integral part of DD4hep is DDG4 which is a powerful tool that converts arbitrary DD4hep detector geometries to Geant4 and provides access to all Geant4 action stages. It is equipped with a comprehensive plugins suite that includes handling of different IO formats; Monte Carlo truth linking and a large set of segmentation and sensitive detector classes, allowing the simulation of a wide variety of detector technologies. In the following, recent developments in DD4hep/DDG4 like the addition of a ROOT based persistency mechanism for the detector description and the development of framework support for DDG4 are highlighted. Through this mechanism an experiment’s data processing framework can interface its essential tools to all DDG4 actions. This allows for simple integration of DD4hep into existing experiment frameworks.
Calorimeter fast simulation based on hit libraries LHCb Gauss framework
Authors: Rama Matteo , Vitali Giacomo
Published: September 2019

In HEP experiments the CPU resources required by Monte Carlo simulations are taking up an ever larger fraction of the total computing power (greater than 75%). At the same time the pace of performance improvements given by technology is slowing down, so the only solution is a more efficient use of resources. In this context we present the ongoing development of a fast simulation of the LHCb calorimeter based on a point library, which has significant advantages in terms of library size and output accuracy compared to the cell hit library. Preliminary performance studies are presented.
The JINR distributed computing environment
Authors: Korenkov Vladimir , Dolbilov Andrei , Mitsyn Valeri , Kashunin Ivan , Kutovskiy Nikolay , Podgainy Dmitry , Streltsova Oksana , Strizh Tatiana , Trofimov Vladimir , Zrelov Peter
Published: September 2019

Computing in the field of high energy physics requires usage of heterogeneous computing resources and IT, such as grid, high performance computing, cloud computing and big data analytics for data processing and analysis. The core of the distributed computing environment at the Joint Institute for Nuclear Research is the Multifunctional Information and Computing Complex. It includes Tier1 for CMS experiment, Tier2 site for all LHC experiments and other grid non-LHC VOs, such as BIOMED, COMPASS, NICA/MPD, NOvA, STAR and BESIII, as well as cloud and HPC infrastructures. A brief status overview of each component is presented. Particular attention is given to the development of distributed computations performed in collaboration with CERN, BNL, FNAL, FAIR, China, and JINR Member States. One of the directions for the cloud infrastructure is the development of integration methods of various cloud resources of the JINR Member State organizations in order to perform common tasks, and also to distribute a load across integrated resources. We performed cloud resources integration of scientific centers in Armenia, Azerbaijan, Belarus, Kazakhstan and Russia. Extension of the HPC component will be carried through a specialized infrastructure for HPC engineering that is being created at MICC, which makes use of the contact liquid cooling technology implemented by the Russian company JSC "RSC Technologies". Current plans are to further develop MICC as a center for scientific computing within the multidisciplinary research environment of JINR and JINR Member States, and mainly for the NICA mega-science project.
Harvester : an edge service harvesting heterogeneous resources for ATLAS
Authors: Maeno Tadashi , Barreiro Megino Fernando Harald , Benjamin Doug , Cameron David , Childers John Taylor , De Kaushik , De Salvo Alessandro , Filipcic Andrej , Hover John , Lin FaHui , Oleynik Danila
Published: September 2019

The Production and Distributed Analysis (PanDA) system has been successfully used in the ATLAS experiment as a data-driven workload management system. The PanDA system has proven to be capable of operating at the Large Hadron Collider data processing scale over the last decade including the Run 1 and Run 2 data taking periods. PanDA was originally designed to be weakly coupled with the WLCG processing resources. Lately the system is revealing the difficulties to optimally integrate and exploit new resource types such as HPC and preemptible cloud resources with instant spin-up, and new workflows such as the event service, because their intrinsic nature and requirements are quite different from that of traditional grid resources. Therefore, a new component, Harvester, has been developed to mediate the control and information flow between PanDA and the resources, in order to enable more intelligent workload management and dynamic resource provisioning based on detailed knowledge of resource capabilities and their real-time state. Harvester has been designed around a modular structure to separate core functions and resource specific plugins, simplifying the operation with heterogeneous resources and providing a uniform monitoring view. This paper will give an overview of the Harvester architecture, current status with various resources, and future plans.
GRACC: GRid ACcounting Collector
Authors: Weitzel Derek , Bockelman Brian , Zvada Marian , Retzke Kevin , Bhat Shreyas
Published: September 2019

The OSG has long maintained a central accounting system called Gratia. It uses small probes on each computing and storage resource in order to collect resource usage. The probes report to a central collector which stores the usage in a database. The database is then queried to generate reports. As the OSG aged, the size of the database grew very large. It became too large for the database technology to efficiently query to generate detailed reports. The design of a replacement requires data storage that could be queried efficiently to generate multi-year reports. Additionally, it requires flexibilityto add new attributes to the collected data.

In this paper we will describe updates to the GRACC architecture in the last 18 months. GRACC uses modern web technologies that were designed for large data storage, query, and visualization. That includes the open source database Elasticsearch, message broker software RabbitMQ, and Grafana and Kibana as data visualization platforms. It uses multiple agents that perform operations on the data to transform it for easier querying and summarization.
The next generation PanDA Pilot for and beyond the ATLAS experiment
Authors: Nilsson Paul , Anisenkov Alexey , Benjamin Doug , Drizhuk Daniel , Guan Wen , Lassnig Mario , Oleynik Danila , Svirin Pavlo , Wegner Tobias
Published: September 2019

The Production and Distributed Analysis system (PanDA) is a pilot-based workload management system that was originally designed for the ATLAS Experiment at the LHC and to use with grid sites. Since the coming LHC data taking runs will require more resources than grid computing alone can provide, the various LHC experiments are engaged in an ambitious program to extend the computing model to include opportunistically used resources such as High Performance Computers (HPCs), clouds and volunteer computers. To this end, PanDA is being extended beyond grids and ATLAS to be used on the new types of resources as well as by other experiments. A new key component is being developed, the next generation PanDA Pilot (Pilot 2). Pilot 2 is a complete rewrite of the original PanDA Pilot which has been used in the ATLAS Experiment for over a decade. The new Pilot architecture follows a component-based approach which improves system flexibility, enables a clear workflow control, evolves the system according to modern functional use-cases to facilitate coming feature requests from new and old PanDA users. This paper describes Pilot 2, its architecture and place in the PanDA hierarchy. Furthermore, its ability to be used either as a command tool or through APIs is explained, as well as how its workflows and components are being streamlined for usage on both grids and opportunistically used resources for and beyond the ATLAS experiment.
HEPCloud, an Elastic Hybrid HEP Facility using an Intelligent Decision Support System
Authors: Mhashilkar Parag , Altunay Mine , Berman Eileen , Dagenhart David , Fuess Stuart , Holzman Burt , Kowalkowski James , Litvintsev Dmitry , Lu Qiming , Moibenko Alexander , Paterno Marc , Spentzouris Panagiotis , Timm Steven , Tiradani Anthony , Vaandering Eric , Hover John , Bejar Jose Caballero
Published: September 2019

HEPCloud is rapidly becoming the primary system for provisioning compute resources for all Fermilab-affiliated experiments. In order to reliably meet the peak demands of the next generation of High Energy Physics experiments, Fermilab must plan to elastically expand its computational capabilities to cover the forecasted need. Commercial cloud and allocation-based High Performance Computing (HPC) resources both have explicit and implicit costs that must be considered when deciding when to provision these resources, and at which scale. In order to support such provisioning in a manner consistent with organizational business rules and budget constraints, we have developed a modular intelligent decision support system (IDSS) to aid in the automatic provisioning of resources spanning multiple cloud providers, multiple HPC centers, and grid computing federations. In this paper, we discuss the goals and architecture of the HEPCloud Facility, the architecture of the IDSS, and our early experience in using the IDSS for automated facility expansion both at Fermi and Brookhaven National Laboratory.
Grid production with the ATLAS Event Service
Authors: Fullana Torregrosa Esteban , Benjamin Doug , Calafiura Paolo , Childers Taylor , De Kaushik , Di Girolamo Alessandro , Garcia Navarro Jose-Enrique , Guan Wen , Lassnig Mario , Maeno Tadashi , Nilsson Paul , Tsulaia Vakhtang , Van Gemmeren Peter , Wenaus Torre , Yang Wei
Published: September 2019

ATLAS has developed and previously presented a new computing architecture, the Event Service, that allows real time delivery of fine grained workloads which process dispatched events (or event ranges) and immediately streams outputs. The principal aim was to profit from opportunistic resources such as commercial cloud, supercomputing, and volunteer computing, and otherwise unused cycles on clusters and grids. During the development and deployment phase, its utility also on the grid and conventional clusters for the exploitation of otherwise unused cycles became apparent. Here we describe our experience commissioning the Event Service on the grid in the ATLAS production system. We study the performance compared with standard simulation production. We describe the integration with the ATLAS data management system to ensure scalability and compatibility with object stores. Finally, we outline the remaining steps towards a fully commissioned system.
The Data Ocean Project
Authors: Barisits Martin , Barreiro Fernando , Beermann Thomas , Bhatia Karan , De Kaushik , Dubreuil Arnaud , Elmsheuser Johannes , Klimentov Alexei , Lassnig Mario , Love Peter , Maeno Tadashi , Manzi Andrea , Mashinistov Ruslan , Murphy Andy , Nilsson Paul , Panitkin Sergey , Wegner Tobias
Published: September 2019

Transparent use of commercial cloud resources for scientific experiments is a hard problem. In this article, we describe the first steps of the Data Ocean R&D collaboration between the high-energy physics experiment ATLAS together with Google Cloud Platform, to allow seamless use of Google Compute Engine and Google Cloud Storage for physics analysis. We start by describing the three preliminary use cases that were identified at the beginning of the project. The following sections then detail the work done in the data
management system Rucio and the workflow management systems PanDA and Harvester to interface Google Cloud Platform with the ATLAS distributed computing environment, and show the results of the integration tests. Afterwards, we describe the setup and results from a full ATLAS user analysis that was executed natively on Google Cloud Platform, and give estimates on projected costs. We close with a summary and and outlook on future work.
WLCG space accounting in the SRM-less world
Authors: Andreeva Julia , Christidis Dimitrios , Di Girolamo Alessandro , Keeble Oliver
Published: September 2019

The WLCG computing infrastructure provides distributed storage capacity hosted at the geographically dispersed computing sites. In order to effectively organize storage and processing of the LHC data, the LHC experiments require a reliable and complete overview of the storage capacity in terms of the occupied and free space, the storage shares allocated to different computing activities, and the possibility to detect “dark” data that occupies space while being unknown to the experiment's file catalogue. The task of the WLCG space accounting activity is to provide such an overview and to assist LHC experiments and WLCG operations to manage storage space and to understand future requirements.

Several space accounting solutions which have been developed by the LHC experiments are currently based on Storage Resource Manager (SRM). In the coming years SRM becomes an optional service for sites which do not provide tape storage. Moreover, already now some of the storage implementations do not provide an SRM interface. Therefore, the next generation of the space accounting systems should not be based on SRM. In order to enable possibility for exposing storage topology and space accounting information the Storage Resource Reporting proposal has been agreed between LHC experiments, sites and storage providers. This contribution describes the WLCG storage resource accounting system which is being developed based on Storage Resource Reporting proposal.
Remote data access in computational jobs on the ATLAS data grid
Authors: Begy Volodimir , Barisits Martin , Lassnig Mario , Schikuta Erich
Published: September 2019

This work describes the technique of remote data access from computational jobs on the ATLAS data grid. In comparison to traditional data movement and stage-in approaches it is well suited for data transfers which are asynchronous with respect to the job execution. Hence, it can be used for optimization of data access patterns based on various policies. In this study, remote data access is realized with the HTTP and WebDAV protocols, and is investigated in the context of intra- and inter-computing site data transfers. In both cases, the typical scenarios for application of remote data access are identified. The paper also presents an analysis of parameters influencing the data goodput between heterogeneous storage element - worker node pairs on the grid.
The GridKa Tape System: status and outlook
Authors: Ressmann Doris , Lobontu Dorin , Beitzinger Martin , Schaefer Karin , Heiss Andreas , Petzold Andreas , Musheghyan Haykuhi
Published: September 2019

Tape storage is still a cost effective way to keep large amounts of data over a long period of time and it is expected that this will continue in the future. The GridKa tape environment is a complex system of many hardware components and software layers. Configuring this system for optimal performance for all use cases is a non-trivial task and requires a lot of experience. We present the current status of the GridKa tape environment, report on recent upgrades and improvements and plans to further develop and enhance the system, especially with regard to the future requirements of the HEP experiments and their large data centers. The short-term planning mainly includes the transition from TSM to HPSS as the backend and the effects on the connection of dCache and xrootd. Recent changes of the vendor situation of certain tape technologies require a precise analysis of the impact and eventual adaptation of the mid-term planning, in particular with respect to scalability challenge that comes with HL-LHC on the horizon.
CERNBox: the CERN cloud storage hub
Authors: Labrador Hugo González , Alexandropoulos Georgios , Bocchi Enrico , Castro Diogo , Chan Belinda , Contescu Cristian , Lamanna Massimo , Lo Presti Giuseppe , Mascetti Luca , Moscicki Jakub , Musset Paul , Karavakis Edward , Pelletier Remy , Valverde Roberto
Published: September 2019

CERNBox is the CERN cloud storage hub. It allows synchronizing and sharing files on all major desktop and mobile platforms (Linux, Windows, MacOSX, Android, iOS) aiming to provide universal access and offline availability to any data stored in the CERN EOS infrastructure. With more than 16000 users registered in the system, CERNBox has responded to the high demand in our diverse community to an easily and accessible cloud storage solution that also provides integration with other CERN services for big science: visualization tools, interactive data analysis and real-time collaborative editing. Collaborative authoring of documents is now becoming standard practice with public cloud services, and within CERNBox we are looking into several options: from the collaborative editing of shared office documents with different solutions (Microsoft, OnlyOffice, Collabora) to integrating mark-down as well as LaTeX editors, to exploring the evolution of Jupyter Notebooks towards collaborative editing, where the latter leverages on the existing SWAN Physics analysis service. We report on our experience managing this technology and applicable use-cases, also in a broader scientific and research context and its future evolution with highlights on the current development status and future road map. In particular we will highlight the future move to an architecture based on micro services to easily adapt and evolve the service to the technology and usage evolution, notably to unify CERN home directory services.