bluuebunny/crossref_metadata_2025 huggingface dataset:
Tungsten Electron Emitter (TE2) with direct heated cathode by plasma stream
Authors: Thoma K I , Dönges T , Droba M , Meusel O , Podlech H , Schulte-Urlichs K
Published: January 2023

At Goethe-University, a novel concept of heating metallic cathodes is currently under investigation. In the scope of the ARIES collaboration WP16, an RF-modulated electron gun was developed and manufactured for application in electron lenses for space charge compensation. The goal of this project is to increase the intensity of primary beams, especially in low energy booster synchrotrons like the SIS18 and SIS100 at GSI/FAIR or the SPS at CERN. The gun was designed to produce electron currents of 10 A at extraction voltages of 30 kV. The tungsten electron emitter (TE2) and the grid electrode were designed and manufactured to be integrated in the extractor of the original volume type ion source. Significant effort was put into a robust and flexible design with highly reliable key components. The cathode is heated by a plasma stream generated in the plasma chamber of the source. Different heating options of the cathode are currently being studied. This contribution presents the working principles of the electron gun and first measurements results of cathode heating.
Performance of automated synchrotron lattice optimisation using genetic algorithm
Authors: Zhang X , Sheehy S L
Published: January 2023

Rapid advances in superconducting magnets and related accelerator technology opens many unexplored possibilities for future synchrotron designs. We present an efficient method to probe the feasible parameter space of synchrotron lattice configurations. Using this method, we can converge on a suite of optimal solutions with multiple optimisation objectives. It is a general method that can be adapted to other lattice design problems with different constraints or optimisation objectives. In this method, we tackle the lattice design problem using a multi-objective genetic algorithm. The problem is encoded by representing the components of each lattice as columns of a matrix. This new method is an improvement over the neural network based approach in terms of computational resources. We evaluate the performance and limitations of this new method with benchmark results.
High current heavy ion beam investigations at GSI-UNILAC
Authors: Vormann H , Barth W , Miski-Oglu M , Scheeler U , Vossberg M , Yaramyshev S
Published: January 2023

The GSI Universal Linear Accelerator UNILAC and the synchrotron SIS18 will serve as injector for the upcoming FAIR-facility. The UNILAC-High Current Injector will be improved and modernized until FAIR is commissioned and the Alvarez post stripper accelerator is replaced. The reference heavy ion for future FAIR-operation is uranium, with highest intensity requirements. To re-establish uranium beam operation and to improve high current beam operation, different subjects have been explored in dedicated machine investigation campaigns. After a beam line modification in 2017 the RFQ-performance had deteriorated significantly; new rods have been installed and the RF-working point has been redefined. Also the Superlens-performance had become unsatisfactory; improved with a modified RF-coupler. With a pulsed hydrogen gas stripper target the uranium beam stripping efficiency could be increased by 65%. Various work has already been carried out to establish this stripper device in routine operation. With medium heavy ion beams a very high beam brilliance at the end of transfer line to SIS18 was achieved. Results of the measurement campaigns and the UNILAC upgrade activities will be presented.
Design and beam dynamics study of disk-loaded structure for muon LINAC
Authors: Sumi K , Iijima T , Inami K , Sue Y , Yotsuzuka M , Ego H , Otani M , Saito N , Mibe T , Yoshida M , Kondo Y , Moriya K , Takeuchi Y , Nakazawa Y , Yasuda H
Published: January 2023

The disk-loaded structures (DLS) in the muon LINAC are under development for the J-PARC muon g–2/EDM experiment. Four DLSs with an accelerating gradient of 20 MV/m take charge of muon acceleration from 40 MeV to 212 MeV, which corresponds to 70% to 94% of the speed of light. The quasi-constant gradient type TM01-2π/3 mode DLSs with gradually varying disk spacing was designed and it was confirmed that the cumulative phase slip due to the mismatch between muon and phase velocity can be suppressed to less than 2 degrees at the frequency of 2592 MHz. In addition, the optimum synchronous phase and the lattice were investigated to satisfy the requirements of the total emittance less than 1.5π mm mrad and the momentum spread less than 0.1% in RMS.
The Zgoubidoo python framework for ray-tracing simulations with Zgoubi: applications to fixed-field accelerators
Authors: Vanwelde M , Hernalsteens C , Tesse R , Gnacadja E , Ramoisiaux E , Pauly N
Published: January 2023

The study of beam dynamics in accelerators featuring main magnets with complex geometries such as Fixed Field Accelerators (FFAs) requires simulation codes allowing step-by-step particle tracking in complex magnetic fields, such as the Zgoubi ray-tracing code. To facilitate the use of Zgoubi and to allow readily processing the resulting tracking data, we developed a modern Python 3 interface, Zgoubidoo, using Zgoubi in the backend. In this work, the key features of Zgoubidoo are illustrated by detailing the main steps to obtain a non-scaling FFA accelerator from a scaling design. The results obtained are in excellent agreement with prior results, including the tune computation and orbit shifts. These results are enhanced by Zgoubidoo beam dynamics analysis and visualization tools, including the placement of lattice elements in a global coordinate system and the computation of linear step-by-step optics. The validation of Zgoubidoo on conventional scaling and non-scaling FFA designs paves the way for future uses in innovative FFA design studies.
Recent results of beam loss mitigation and extremely low beam loss operation of J-PARC RCS
Authors: Saha P K , Okabe K , Nakanoya T , Shobuda Y , Harada H , Tamura F , Okita H , Yoshimoto M , Hotchi H
Published: January 2023

In the 3-GeV RCS (Rapid Cycling Synchrotron) at J-PARC (Japan Proton Accelerator Research Complex), multi-turn H− charge-exchange injection is performed by using a thin stripped foil. The residual radiation at the injection area caused by the uncontrolled beam loss occurred by foil scattering of the circulating beam is a serious issue for regular maintenance works. In addition, the beam loss at the collimator section and its downstream caused for a large emittance beam also should be reduced, especially at high intensity operation. For that purpose we have minimized injection beam size and implemented a smaller size stripper foil. The circulating beam hitting rate is reduced by using a smaller foil, while an optimized vertical angle of the smaller injection beam for vertical transverse painting also gave a reduction of the circulating beam emittances and resulted a further significant beam loss mitigation at the collimator section and its downstream. As a result, the residual radiation after user operation at 700 kW beam power was also measured to be significantly reduced.
WITHDRAWN: Investigation of spin-decoherence in the NICA storage ring for the future EDM-measurement experiment
Authors: Aksentev A E , Melnikov A A , Senichev Y V , Ladygin V P , Syresin E M
Published: January 2023

This article has been withdrawn by IOP Publishing following the request by the authors to augment their affiliation by an institution. Upon reviewing the matter, IOP Publishing found that the institution (Moscow Institute of Physics and Technology) is subject to sanctions by the UK government.

To ensure compliance with sanctions regulations, this article has been withdrawn from IOPscience.
Horizontal beam response at extraction conditions at the Heidelberg Ion-beam Therapy Centre
Authors: Cortés García E C , Feldmeier E , Haberer Th
Published: January 2023

The Heidelberg Ion-Beam Therapy Centre’s synchrotron makes use of the sextupole driven RF-KO method near the third-order resonance in order to slowly extract the beam that is delivered to the patients. The horizontal beam response of a coasting beam was studied experimentally and with simulations at extraction conditions in order to deduce regions of interest for an optimal excitation signal spectrum. Two narrow frequency regions were found where the beam reacts coherently. With these information an RF signal was proposed for the resonant slow extraction.
Parallelization of Radia magnetostatics code
Authors: Banerjee A , Chubar O , Le Bec G , Chavanne J , Nash B , Hall C , Edelen J
Published: January 2023

Radia 3D magnetostatics code has been used for the design of insertion devices for light sources over more than two decades. The code uses the magnetization integral approach that is efficient for solving permanent magnet and hybrid magnet structures. The initial version of the Radia code was sequential, its core written in C++ and interface in the Mathematica language. This paper describes a new Python interfaced parallel version of Radia and its applications. The parallelization of the code was implemented on C++ level, where the semi-analytical calculations of interaction matrix elements and resultant magnetic fields were parallelized using the Message Passing Interface. The parallel performance results are encouraging, particularly for magnetic field calculation post relaxation where a ∼600 speedup with respect to sequential execution was obtained. The new parallel Radia version facilitates designs of insertion devices and lattice magnets for novel particle accelerators.
Modeling a Nb3Sn cryounit in GPT at UITF
Authors: Pokharel S , Hofler A S , Krafft G A
Published: January 2023

Nb3Sn is a prospective material for future superconducting radio frequency (SRF) accelerator cavities. Compared to conventional niobium, the material can achieve higher quality factors, higher temperature operation, and potentially higher accelerating gradients (Eacc ≈ 96 MV/m). In this work, we performed modeling of the Upgraded Injector Test Facility (UITF) at Jefferson Lab utilizing newly constructed Nb3Sn cavities. We studied the effects of the buncher cavity and varied the gun voltage from 200-500 keV. We have calibrated and optimized the SRF cavity gradients and phases for the Nb3Sn five-cell cavities’ energy gains with the framework of the General Particle Tracer (GPT). Our calculations show the beam goes cleanly through the unit. There is full energy gain out of the second SRF cavity but not from the first SRF cavity due to non-relativistic phase shifts.
Review of alignment and stability tolerances for advanced light sources
Authors: Khan A , Sharma S , Smaluk V
Published: January 2023

Alignment and mechanical-stability specifications are essential to the performance of low-emittance storage rings. Beam dynamics simulations are usually performed to establish these specifications. However, the simulation procedures and the input parameters related to magnet positions are not well established which leads to differences in the final specifications. In this paper we discuss important parameters of the mechanical/structural systems of the storage ring that impact on the alignment and stability specification. We reviewed the alignment and stability specifications used at modern light sources across the world that will help to propose an efficient model for a low-emittance upgrade of NSLS-II.
Space charge analysis for low energy photoinjector
Authors: Carillo M , Behtouei M , Bosco F , Faillace L , Ficcadenti L , Fukasaway A , Giuliano L , Mostacci A , Migliorati M , Spataro B , Rosenzweig J , Palumbo L
Published: January 2023

Beam dynamics studies are performed in the context of a C-Band hybrid photo-injector project developed by a collaboration between UCLA/Sapienza/INFN-LNF/RadiaBeam [1, 2]. These studies aim to explain beam behaviour through the beam-slice evolution, using analytical and numerical approaches. An understanding of the emittance oscillations is obtained starting from the slice analysis, which allows correlation of the position of the emittance minima with the slope of the slices in the transverse phase space (TPS). At the end, a significant reduction in the normalized emittance is obtained by varying the transverse shape of the beam while assuming a longitudinal Gaussian distribution. Indeed, the emittance growth due to nonlinear space-charge fields has been found to occur immediately after moment of the beam emission from the cathode, giving insight into the optimum laser profile needed for minimizing the emittance.
Modeling and mitigation of long-range wakefields for advanced linear colliders
Authors: Bosco F , Camacho O , Carillo M , Chiadroni E , Faillace L , Fukasawa A , Giribono A , Giuliano L , Majernik N , Mostacci A , Palumbo L , Rosenzweig J , Spataro B , Vaccarezza C , Migliorati M
Published: January 2023

The luminosity requirements of TeV-class linear colliders demand use of intense charged beams at high repetition rates. Such features imply multi-bunch operation with long current trains accelerated over the km length scale. Consequently, particle beams are exposed to the mutual parasitic interaction due to the long-range wakefields excited by the leading bunches in the accelerating structures. Such perturbations to the motion induce transverse oscillations of the bunches, potentially leading to instabilities such as transverse beam break-up. Here we present a dedicated tracking code that studies the effects of long-range transverse wakefield interaction among different bunches in linear accelerators. Being described by means of an efficient matrix formalism, such effects can be included while preserving short computational times. As a reference case, we use our code to investigate the performance of a state-of-the-art linear collider currently under design and, in addition, we discuss possible mitigation techniques based on frequency detuning and damping.
Lattice design of the UVSOR-IV storage ring
Authors: Salehi E , Taira Y , Fujimoto M , Guo L , Katoh M.
Published: January 2023

We are designing a storage ring lattice for the future plan of UVSOR. As a candidate, we have designed a storage ring of 1 GeV electron energy, which is higher than the present value, 750 MeV. The magnetic lattice is based on a compact double bend achromat cell, which consists of two bending magnets and four focusing magnets, all of which are of combined function. The circumference is 82.5 m. The emittance is 4 nm in the achromatic condition, which becomes lower in the non-achromatic condition. The lattice has moderately large dynamic aperture with four sextupole families. The lattice of 6-fold symmetry has six straight sections of 4 m long and six of 1.5 m long. Undulators can radiate nearly diffraction-limited light in VUV. If we install high field multipole wigglers at the short straight sections, they can provide high flux tender X-rays. We are expecting usage of a laser-based accelerator as the injector, which might be developed in the next decade. As an alternative plan, we have designed a traditional injector, which consists of a linear accelerator and a booster synchrotron that can be constructed inside of the storage ring.
A method for obtaining 3D charge density distribution of a self-modulated proton bunch
Authors: Nechaeva T , Verra L , Porta G Zevi Della , Muggli P
Published: January 2023

The Advanced Wakefield Experiment (AWAKE) at CERN is the first plasma wakefield accelerator experiment to use a proton bunch as driver. The long bunch undergoes seeded self-modulation (SSM) in a 10 m-long plasma. SSM transforms the bunch into a train of short micro-bunches that resonantly drive high-amplitude wakefields. We use optical transition radiation (OTR) and a streak camera to obtain time-resolved images of the bunch transverse charge density distribution in a given plane. In this paper we present a method to obtain 3D images of the bunch by scanning the OTR across the entrance slit of the streak camera. Reconstruction of the 3D distribution is possible because with seeding self-modulation is reproducible. The 3D images allow for checking the axi-symmetry of SSM and for detecting the possible presence of the non-axi-symmetric hosing instability (HI).
Surrogate-based Bayesian inference of transverse beam distribution for non-stationary accelerator systems
Authors: Fujii H , Fukunishi N , Yamakita M
Published: January 2023

Constraints on the beam diagnostics available in real-time and time-varying beam source conditions make it difficult to provide users with high-quality beams for long periods without interrupting experiments. Although surrogate model-based inference is useful for inferring the unmeasurable, the system states can be incorrectly inferred due to manufacturing errors and neglected higher-order effects when creating the surrogate model. In this paper, we propose to adaptively assimilate the surrogate model for reconstructing the transverse beam distribution with uncertainty and underspecification using a sequential Monte Carlo from the measurements of quadrant beam loss monitors. The proposed method enables sample-efficient and training-free inference and control of the time-varying transverse beam distribution.
Online optimization of NSLS-II dynamic aperture and injection transient
Authors: Yang X , Wang G , Smaluk V , Yu L H , Shaftan T , Li Y , Plassard F , Buda S , Hidaka Y , Durfee D , Tian Y , Hu Y , Ha K , Derbenev A , Bacha B , Danneil C , Padrazo D
Published: January 2023

The goal of the NSLS-II online optimization project is to improve the beam quality for the user experiments. To increase the beam lifetime and injection efficiency, we have developed a model-independent online optimization of nonlinear beam dynamics using advanced algorithms, such as Robust Conjugate-Gradient Algorithm (RCDS). The optimization objective is the injection efficiency and optimization variables are the sextupole magnet strengths. Using the online optimization technique, we increased the NSLS-II dynamic aperture and reduced the amplitude-dependent tune shift. Recently, the sextupole optimization was successfully applied to double the injection efficiency up to above 90% for the high-chromaticity lattice being developed to improve the beam stability and to increase the single-bunch beam intensity. Minimizing the beam perturbation during injection is the second objective in this project, realized by online optimization of the injection kickers. To optimize the full set of kicker parameters, including the trigger timing, amplitude, and pulse width, we upgraded all kicker power supplies with the capability of tunable waveform width. As a result, we have reduced the injection transient by a factor of 29, down to the limit of 60 μm.
Ultra-fast generator for impact ionization triggering
Authors: del Barrio Montañés A A , Senaj V , Kramer T , Dutheil Y , Sack M
Published: January 2023

Impact ionization triggering can be successfully applied to standard thyristors, thus boosting their dI/dt capability by up to 1000x. This ground-breaking triggering requires applying significant overvoltage on the anode-cathode of a thyristor with a slew rate > 1 kV/ns. Compact pulse generators based on commercial off-the-shelf (COTS) components would allow the spread of this technology into numerous applications, including fast kicker generators for particle accelerators. In our approach, the beginning of the triggering chain is an HV SiC MOS with an ultra-fast super-boosting gate driver. The super boosting of a 1.7 kV rated SiC MOS allows to reduce the MOS rise time by a factor of > 26 (datasheet tr = 20 ns vs. measured tr < 800 ps), resulting in an output voltage slew rate > 1 kV/ns and an amplitude > 1 kV. Additional boosting is obtained by a Marx generator with GaAs diodes, reaching an output voltage slew rate > 11 kV/ns. The final stage will be a Marx generator with medium size thyristors triggered in impact ionization mode with sufficient voltage and current rating necessary for the triggering of a high power thyristor. This paper presents the impact ionization triggering of a small size thyristor.
Proposal of a VHEE Linac for FLASH radiotherapy
Authors: Giuliano L , Bosco F , Carillo M , Arcangelis D De , Ficcadenti L , Francescone D , Gregorio A De , Franciosini G , Migliorati M , Mostacci A , Palumbo L , Patera V , Sarti A , Alesini D , Behtouei M , Faillace L , Gallo A , Spataro B , Vannozzi A , Cirrone P , Cuttone G , Torrisi G , Bisogni M G , Pensavalle J H , Martino F Di , Favaudon V , Heinrich S , Patriarca A
Published: January 2023

Translation of electron FLASH radiotherapy in clinical practice requires the use of high energy accelerators to treat deep tumours and Very High Electron Energy (VHEE) could represent a valid technique to achieve this goal. In this scenario, a VHEE FLASH linac is under study at the University La Sapienza of Rome (Italy) in collaboration with the Italian Institute for Nuclear Research (INFN) and the Institut Curie (France). Here we present the preliminary results of a compact C-band system aiming to reach an high accelerating gradient and an high pulse current necessary to deliver high dose per pulse and ultra-high dose rate required for FLASH effect. We propose a system composed of a low energy high current injector linac followed by a modular section of high accelerating gradient structures. CST code is used to define the required LINAC’s RF parameters and beam dynamics simulations are performed using TSTEP and ASTRA.
Tuning of superconducting cavities using the FFT of transmitted power
Authors: Laface E , Maiano C G , Pierini P , Wang M
Published: January 2023

We implemented a method to tune the ESS superconducting cavities based on the spectral analysis of the high resolution data available from the Low Level RF system (LLRF) for the transmitted power, without the need of connecting a network analyzer or any other dedicated instrumentation along the RF chain. A frequency peak up to 4 MHz off from the resonating frequency can be detected and used to control the stepper motor of the tuner until the cavity is stretched to the proper length to reach the correct operation frequency. Experience of its use at the ESS Test Stand 2 (TS2) facility at Lund during cryomodule acceptance testing is presented.
Design studies on a high-power wide-band RF combiner for consolidation of the driver amplifier of the J-PARC RCS
Authors: Okita H , Tamura F , Yamamoto M , Nomura M , Shimada T , Yoshii M , Ohmori C , Sugiyama Y , Hasegawa K , Hara K , Paoluzzi M M
Published: January 2023

A power upgrade of the existing 8-kW solid-state driver amplifier is required for the acceleration of high intensity proton beams on the J-PARC 3-GeV Rapid Cycling Synchrotron. The development of a 25-kW amplifier with gallium nitride (GaN) HEMTs, based on 6.4-kW modules is ongoing. The combiner is a key component to achieve such a high output power over the wide bandwidth required for multi-harmonic RF operation. This paper presents the preliminary design of the combiner. The circuit simulation setup and results, including the realistic magnetic core characteristics and frequency response of the cable, are reported.
Design of the 590 MeV proton beamline for the proposed TATTOOS isotope production target at PSI
Authors: Hartmann M , Kiselev D , Reggiani D , Snuverink J , Zhang H , Seidel M
Published: January 2023

IMPACT (Isotope and Muon Production with Advanced Cyclotron and Target Technologies) is a proposed initiative envisaged for the high-intensity proton accelerator facility (HIPA) at the Paul Scherrer Institute (PSI). As part of IMPACT, a radioisotope target station, TATTOOS (Targeted Alpha Tumour Therapy and Other Oncological Solutions) will allow the production of terbium radionuclides for therapeutic and diagnostic purposes. The proposed TATTOOS beamline and target will be located near the UCN (Ultra Cold Neutron source) target area, branching off from the main UCN beamline. In particular, the beamline is intended to operate at a beam intensity of 100 μA, requiring a continuous splitting of the main beam via an electrostatic splitter. Realistic beam loss simulations to verify safe operation have been performed and optimised using Beam Delivery Simulation (BDSIM), a Geant4 based tool enabling the simulation of beam transportation through magnets and particle passage through the accelerator. In this study, beam profiles, beam transmission and power deposits are generated and studied.
Energy comparison of room temperature and superconducting synchrotrons for hadron therapy
Authors: Bisoffi G , Benedetto E , Karppinen M , Pullia M G , Khalvati M Reza , Rossi L , Sapinski M , Sorbi M , Valente U , van Weelderen R , Venchi G , Vretenar M
Published: January 2023

The yearly energy requirements of room temperature (RT) and superconducting (SC) magnet options of a new hadron therapy (HT) facility are compared. Special reference is made to the layouts considered for the proposed SEEIIST facility. Benchmarking with the RT CNAO HT centre in Pavia (Italy) was carried out. The energy comparison is centred on the different synchrotron solutions, assuming the same injector and lines in the designs. The beam current is 20 times higher than in present generation facilities: this allows efficient multi-energy extraction (MEE), which shortens the therapy treatment and is needed especially in the SC option, because of the slow magnet ramping time. Hence, power values of the facility in the traditional mode were converted into MEE ones, for a fair comparison between RT and SC magnets. Cryocoolers (c.c.) and a liquefier are also compared, for synchrotron refrigeration. This study shows that a RT facility in MEE mode requires the least average energy, followed by the SC synchrotron solution with a liquefier, while the most energy intensive solution is the SC one with c.c.
Study on construction of an additional beamline for a compact neutron source using a 30 MeV proton cyclotron
Authors: Kuriyama Y , Hino M , Iwashita Y , Nakamura R , Tanaka H
Published: January 2023

The Institute for Integrated Radiation and Nuclear Science, Kyoto University (KURNS) has been actively using neutrons extracted from the research reactor (KUR) for collaborative research. Since the operation of KUR is scheduled to be terminated in 2026 according to the current reactor operation plan, the development of a general-purpose neutron source using the 30 MeV proton cyclotron (HM-30) installed at KURNS for Boron Neutron Capture Therapy (BNCT) research has been discussed as an alternative neutron source. In this presentation, we report on the conceptual design of an additional beamline for a compact neutron source using this cyclotron.
Design of beam collection system with high transmission efficiency and tunablity
Authors: Yan Y , Yang T , Li D Y , Cheng H , Li Y Z , Wu M J , Fang Y L , Li F N , Guo Z , Yuan Z X , Zhu K , Lin C , Yan X Q
Published: January 2023

A beamline is required to focus proton beams produced by laser plasma accelerator to high charge density spots for practical applications. The Compact LAser Plasma Accelerator (CLAPA) coupled with an image-relaying beamline has been built at Peking University. While the collection section of this beamline is an electromagnetic quadrupoles (EMQs) triplet with certain aperture, more than 71 % of the protons are lost in the inlet end face or vacuum tube wall of triplet due to their divergence angles. Here we show the development of a high transmission efficiency and tunable collection system in the beamline by adding two permanent magnet quadrupoles (PMQs) with magnetic field strengths of about 200 and 120 T/m respectively in front of the triplet. As a result, by monitoring the relative position of the PMQs and the currents of the EMQs, the focusing energy is able to be adjusted ranging from 2 to 10 MeV, and the transmission efficiency is 1.4 to 3 times as high as only collected by EMQs triple.
Experimental analysis of the sweepback angle effect on the thrust generation of a robotic penguin wing
Authors: Shen Yayi , Tanaka Hiroto
Published: January 2023

Penguins have evolved excellent swimming skills as diving birds, benefiting from their agile wings. This paper experimentally analyzes the effects of the wing sweepback angle on thrust generation using a robotic penguin wing. A developed wing mechanism that can realize penguin-like flapping and feathering motion was used for actuating five alternative wing models, with different sweepback angles ranging from 0° to 50°. Force measurements under a steady water flow were conducted for both fixed and flapping states for all wing models. The results showed that small sweepback angles of 30° or less in the fixed state caused a steep lift curve and a moderate sweepback angle of 30° produced the largest lift-to-drag ratio. In the flapping state, the smaller sweepback wings generated a larger net thrust for the same wing motion, whereas the larger-sweepback wings produced more thrust under the same Strouhal number. The findings also revealed that larger sweepback wings more easily achieve the maximum net thrust in terms of less angle-of-attack control. In contrast, the hydrodynamic efficiency was not greatly affected by the sweepback. Regardless of the sweepback, the trend of the efficiency increasing with increasing flow speed indicates that the penguin wings can be more suitable for high-speed locomotion for higher hydrodynamic efficiency.
Monitoring Land Subsidence and its Effect on Surabaya Coastal Inundation by Utilizing GPS Campaigns Data
Authors: Riastama C N , Anjasmara I M , Maulida Putra
Published: January 2023

Land subsidence is a process of land movement based on a certain datum (geodetic reference frame) in which there are various variables causing it. This phenomenon occurs in many big cities in Indonesia, which is the city of Surabaya. The Surabaya city has a type of soil in the form of alluvial soil which is prone to movement. The accumulation of land subsidence that occurs will certainly cause its own losses. As a result, it can damage urban infrastructure so that in the future it can cause disruption to the environment, economic activities, and social life in the region. In addition, the Surabaya area is also a coastal area. Coastal areas have characteristics where this area will be strongly influenced by natural events. One of the natural events that affect the oceans and coastal areas is global temperature changes. The phenomenon of global temperature changes can affect sea level rise. If sea level rise occurs accompanied by an increase in the rate of land subsidence, this can result in flooding or inundation in coastal areas. Considering that the city of Surabaya is a metropolitan city that has a high population density and a continuous level of development, mitigation efforts are important in following up on land subsidence in this area. One of the efforts that can be applied is by conducting GPS observations. The outcomes of the GPS observations were then processed using scientific software in the form of GAMIT/GLOBK. According to the study’s findings indicated that Surabaya is experiencing land subsidence in the northern and eastern coastal areas with a range of 0.2 – 83.3 mm/year. The point that experienced a significant decline was in the border area of Tandes and Asemrowo, namely station BM35. Furthermore, land subsidence conditions influence the extent of tidal inundation, where in 2032 tidal inundation will inundate 105.411 km2.
An Estimation of Precipitable Water Vapour Around Surabaya City Using GIPSY-X
Authors: Adhi Dermawan A.A. , Handoko Eko Yuli , Maulida Putra
Published: January 2023

Precipitable water vapor is a crucial climatic parameter that indicates the available humidity in the atmosphere. Precipitable water vapor is produced by evaporation/evapotranspiration from the surface to the atmosphere and thus plays an important role in the water cycle. As an essential indicator of climate change, water vapor contributes significantly to the thermodynamics of the atmosphere. Zenith Total Delay can be calculated using the Precise Point Positioning strategy and all parameters. Using the parameter mapping function, Slant Tropospheric Delay can be converted to Zenith Total Delay, which is affected by temperature, pressure, and humidity. We processed the GNSS data from five stations surrounding Surabaya City using GipyX. Advanced processing generates five minutes of ZTD estimation on each station for five years of observation. A high correlation of ZTD estimated using GipsyX (corr = 0.88) with ZTD at meteorological rinex data of DARW station shows our estimation’s promising and dependable result. The ZTD time series shows consistent patterns on each station, showing the significant contribution of regional signals such as monsoon and ENSO.
The Use of Sentinel-1 in Response to Sequences of Natural Disasters in Indonesia: The South Kalimantan Floods and The Mamuju-Majene Earthquake
Authors: Hayati Noorlaila , Ghifary Royyan M. , Arief Rahmat , Darminto Mohammad Rohmaneo
Published: January 2023

A series of floods occurred in the early year of 2021 are the first major South Kalimantan flood in the past fifty years. The major regions which were affected by them are Banjarmasin, Central Hulu Sungai Regency, and Tanah Laut. There are 211,670 people severely affected by flooding and some of them need to be evacuated to higher zones. Not only floods as a concern of Indonesia National Disaster Management Authority (BNPB) but also earthquake that struck the Mamuju and Majene Regency, in the province of West Sulawesi on 14 and 15 January 2021. Damage was reported in 4 regencies which more than 6,000 buildings were destroyed, more than 3,300 were injured, and 105 people were confirmed dead due to this earthquake. Quick monitoring of two events must be conducted in order to support spatial information for BNPB mitigating the disasters. A geodetic ground measurement could be the best result in terms of accuracy and a large-scale map. However, a lack of pre-event measurement and a difficulty to access the primary roads and bridges in the affected regions makes ground survey complicated to be conducted. An alternative solution is using a space-borne remote sensing which its sensor regularly passes the affected regions. We used Synthetic Aperture Radar (SAR) data from Sentinel-1 to regain spatial information before and after disasters in the provinces of South Kalimantan and West Sulawesi such as inundation and deformation areas, respectively. Using an interval of 12 days and the SAR backscatter analysis, we found inundated areas mostly located near to the Barito River and in sub-districts along its tributaries for a case study of South Kalimantan floods. Meanwhile, we detected deformation about -5 cm in the southern part of West Sulawesi using the Differential Interferometric SAR (DInSAR) technique. Due to high decorrelation with the range of coherence values between 0 and 0.2 in the epicenter of earthquake area, the generated interferograms can not confirm the surface displacement caused by the sequence series of foreshocks, mainshocks, and aftershocks in this area.
Preliminary Prioritization on Steam Flood Injection in Oil Field Using Random Forest Regression Method
Authors: Rafi M , Anggoro S , Rochman Juan Pandu Gya Nur
Published: January 2023

Steam flood injection is a method based on thermal recovery that injects steam, or especially water, at particular temperatures through the special injection wells. In this research, the oil field injected in steam flood is a heavy oil maturation with high viscosity, while the preliminary prioritization in steam flood injection in an oil field must be done at certain stages in a particular area in this oil field. This area consists of 8 sub-areas, 1,2,3 north section of the sub-area and 1,2,3,4,5,6,7,8 south section of the sub-area, each of which has a different number of wells and subsurface conditions. The provision to prioritize the injection in certain areas consists of monthly well production data, well location data, and reservoir data. On reservoir data is used a machine learning method that is random forest regression, which aims to generate variable importance, which will be made by grading reservoir properties variables on which are the most important or relevant for use as a parameter to determine the preliminary prioritization. The use of this Random Forest Regression method was combined to get an accuracy score for high-level modelling and correlate the process and results with the original state of on-field development and reservoir properties. The flow of this method is data cleansing, fitting models to data, assessing the quality of fit, generating decision trees, and identifying key variables. The tools used for this method include a programming language, which will do processing and build the variable importance model in the Random Forest Regression method. This can be done in a systematic and structured way. The result of this method shows the variable importance of reservoir properties such as porosity, saturation, and permeability in the form of OOB value calculation. While the final result of all corresponding prioritizations indicates that the 4,5,6 south section sub-areas should be prioritized for steam flood injection first.
Landslide Susceptibility Mapping Using Random Forest Algorithm and Its Correlation With Land Use In Batu City, Jawa Timur
Authors: Riestu IM , Hidayat H
Published: January 2023

Landslides is one of the most detrimental natural disasters because their occurrences are often destructive to natural and artificial structures on earth and reduce the quality of the surrounding environment. Prediction of the level of vulnerability to landslides in an area can be used to reduce losses caused such as material, loss of life and other environmental damage. BPBD Batu City stated that landslides are the most frequent disasters in Batu City. This research is expected to determine the level of vulnerability to landslides in Batu City, East Java and discover the correlation with the land use. Random Forest (RF) is an algorithm that can be used to predict landslide disasters. The disaster occurance data is then linked to the parameters that cause landslides such as slope, rainfall, soil type, lithology, land use, and soil movement susceptibility zones. The dataset is then divided into 70% training data and 30% testing data. The performance test results show that the RF algorithm can be applied to predict landslide-prone areas in Batu City. This can be seen in the results of the accuracy test which obtained a value of 0.8981 and an AUC value of 0.9327. The result shows that the high prone areas are in settlements, industry & public facilities while the low prone areas are in forest.
The Effect of Human Disturbance on the Spatial Distribution of Anoa (Bubalus Sp.) Using MaxEnt Modeling
Authors: Ardiani Diah , Jaelani Lalu Muhamad , Aldiansyah Septianto , Tambunan Mangapul Parlindungan , Indrawan Mochamad , Wibowo Andri A.
Published: January 2023

Anoa (Bubalus sp.) is one of the endemic species of Sulawesi Island, which is protected because it is threatened with extinction. This study aims to determine the possible distribution of anoa habitat based on environmental parameters by considering the influence of human disturbance. Human disturbance to Anoa is in the form of settlement and transportation infrastructure. The purpose of this paper is to observe whether human disturbance has an effect or not on Anoa spatial distribution. Using 98 encounter species data points, the model discovered that settlement and transportation infrastructure contributed only 4.3% and 1.4%, respectively. Meanwhile, elevation, temperature, and water have a dominant contribution that exceeds 90%. This data indicated that the anoa habitat is less sensitive to human disturbance.
Landscape Planning for Tsunami Disasters Mitigation on Denpasar Coastal Zone
Authors: Manan A , Sanjaya H , As-syakur A R
Published: January 2023

The coastal area is a land-sea transition area and has unique characteristics. This area can also be vulnerable, especially if it is directly related to an area with an epicenter that can cause a tsunami. The coastal areas of South Denpasar, Bali are vulnerable to this disaster. The purpose of this study is to characterize landscape plans and landscape-based mitigation plans for the South Denpasar region. The survey method used in this survey is the METLAND method (Metropolitan landscape planning model survey). The research phase includes four phases: preparation phase, analysis phase, integration phase, and landscape planning phase. The planning characteristics of the tsunami mitigation landscape were analyzed using the tsunami vulnerability matrix table. The materials used in this study were Landsat 9 satellite imagery, National Demnas, Batnas, and Indonesia Topographic Map. Denpasar coastal zone based on the results of land use land cover, distance from the river, distance from the coast, elevation, and slope, has a high risk of being affected by the tsunami. The concept of mangrove vegetation needs to be applied, because mangroves have an important role in resisting tsunami waves. In addition, spatial planning and coastal buildings need to be considered in tsunami mitigation.
Distributed flood simulation based on satellite rainfall data at the Ciliwung River Basin, Jawa, Indonesia
Authors: Sulistyowati R , Meliani F , Sapan E G A , Winarno  , Lestari S , Hapsari R I , Cahyaningtiyas I F , Avianti E , Eugenie A , Grace T , Amaliyah R , Djoharin M , Sutejo B , Syamsudin F
Published: January 2023

Recurrent flooding in Jakarta and surrounding areas due to extreme rainfall is simulated by using distributed hydrological model. In the previous studies, the Rainfall-Runoff Inundation (RRI) model has been used for the flood simulation with 1-km spatial resolution, but it has not been comprehensively investigated. In this paper, extreme rainfall data derived from satellite rainfall data of GSMaP, topography, and land derived from the satellite remote sensing data are used as an input for the RRI model. We analyse the flood simulation at Ciliwung River Basin during 6 (Six) periods of extreme rainfall during January – March 2022 and divide between Flood (F) and Non-Flood (NF) periods. We found that the inundation occurred when the rainfall average reaches more than 7.3 mm/hr and concentrated in the Jakarta downtown area, which had induced the inundation around the Ciliwung river basin.
Stonex F6 and iPad Pro M1 2021 for Cave Graffiti Inspection in Barong Cave, West Java, Indonesia
Authors: Jessy Kartini G. A. , Gumilar Irwan , Abidin H. Z. , Yondri Lutfi , Nabil Nugany M. R.
Published: January 2023

Currently, handheld scanning technology is expanding. In 2021, Apple released updated iPad and iPhone models that included LiDAR. In addition to the iPad Pro 2021, the Stonex F6 is also used to scan heritage objects. In this study, an experiment will be conducted to compare the performance of the two tools when scanning graffiti-covered cave walls. This experiment is hoped to be the first step in discovering cave art using iPad or iPhone Pro that included LiDAR. Echo Mantis is the software that is utilized for the processing of the results of the Stonex scan. Data processing on the iPad Pro M1 uses the same application as data acquisition, namely the 3D Scanner App. The analysis of both datasets was performed using the Cloud Compare software and a density analysis based on the number of neighbors. The density point of Stonex F6 is 1707 points and iPad Pro M1 2021 is 27 points at a radius of 2 cm. According to the results of the study, Stonex F6 has a higher point density than the iPad Pro M1 2021, but the lack of light presents the greatest challenge to data acquisition using Stonex F6. In contrast, due to the good camera resolution of the iPad Pro M1 2021, its point cloud coloring is better compared to that of the Stonex F6.
Analysis of The Effect of Deforestation Rates on Air Pollution Concentration and Land Surface Temperature Using Landsat-8 Imagery with Google Earth Engine (Case Study: East Kalimantan Province, 2019-2020)
Authors: Viedra Ghinaa Gooniyyah Zalsabilla , Sukojo Bangun Muljo
Published: January 2023

The increase in population triggers an increase in deforestation rates. According to data from Ministry of Environment and Forestry, East Kalimantan’s highest deforestation rate reached 54.8 thousand hectares in 2018-2019. This study analyzed the effect of deforestation rates on air pollutant concentrations (SO2 and NO2) and land surface temperature (LST) in East Kalimantan in 2019-2020 with Google Earth Engine (GEE) platform using Landsat 8 Level 2 surface reflectance imagery. The TIR channel was converted into brightness temperature which further used as the input in LST estimation using Mono-Window Algorithm, SO2 estimation using Hasan Algorithm (2014), and NO2 estimation using Alseroury Algorithm (2015). During 2019-2020, the average LST value was 24.2 °C, which was increased by 2.0 °C from the previous year. The maximum NO2 concentration was 189.771 g/m3. The annual average NO2 concentration increased by 0.757 g/m³ from the previous year. The maximum concentration of SO2 was 0.521 ppm. The annual average SO2 concentration increased by 0.011 ppm from the previous year. To determine the effect of deforestation rates on the concentration of SO2, NO2 and LST, the Pearson correlation test was carried out. The correlation coefficient between deforestation rates and SO2 is R = 0.949 (very strong correlation); correlation coefficient between deforestation rates and NO2 is R = 0.889 (very strong correlation); and the correlation coefficient between the deforestation rates and the LST is R = 0.887 (very strong correlation). This shows that the higher deforestation rates, will caused in the higher concentration of SO2, NO2, and LST.
GIS-Based Emergency Hospital Location Suitability Analysis (Case Study: Surabaya City)
Authors: Razzak R R , Pribadi C B , Deviantari U W
Published: January 2023

Indonesia is a country that has been exposed to the COVID-19 virus pandemic, and has positive cases of COVID-19, which are increasing every month. The COVID-19 Handling Task Force confirmed this in 2022. The large number of patients exposed to COVID-19 made the hospital unable to accommodate all patients requiring inpatient treatment, one of the cities that constructed an emergency hospital is the City of Surabaya, which has four emergency hospitals. Surabaya is one of the cities with the most people exposed to the COVID-19 virus. According to the East Java Provincial Government, until 2022, the City of Surabaya was confirmed to have 67,088 cases of COVID-19. According to the mayor of Surabaya, COVID-19 virus patients in the city of Surabaya can be handled well and continue to decline due to the construction of an emergency hospital. The purpose of this paper is to analyze the distribution of the suitability of the location of the emergency hospital to maximize the role of the emergency hospital in the city of Surabaya. The method used is the GIS method, a method that refers to the requirements for the construction of an emergency hospital regulated in the Decree of the Minister of Health of the Republic of Indonesia Number HK.01.07/MENKES/230/2021 concerning Guidelines for the Operation of Field Hospitals/Emergency Hospitals During the Corona Virus Disease Pandemic Period. 2019 (COVID-19). The results showed that four emergency hospitals in the city of Surabaya were by the requirements for the construction of an emergency hospital, namely an emergency hospital located in an area that was in accordance with its designation by the City Spatial Planning and Detailed Map (RDTRK) of the city of Surabaya. From four hospitals emergency, there is no other built area within a radius of 20 meters. From four emergency hospitals, there is no other built area within a radius of 20 meters. It can also be seen that out of the four emergency hospitals, there are public utility networks and drainage canals.