arXiv subjects

Ming-Yang Huang

Publications and source records attributed to Ming-Yang Huang.

17 recordsLinked to original sources

arXiv2020

Study on the anti-correlated painting injection scheme for the Rapid Cycling Synchrotron of the China Spallation Neutron Source

In the rapid cycling synchrotron of the China Spallation Neutron Source, the anti-correlated painting was adopted for the design scheme of the injection system. In the beam commissioning, with the optimization of the anti-correlated painting,the injection beam loss has been well controlled and the injection efficiency has exceeded 99%. Combined with other aspects of adjustments, the beam power on the target has reached 50 kW smoothly. In this paper, we have studied the injection optimization in the beam commissioning. Compared to the simulation results of the design scheme, the transverse beam distribution, transverse coupling effect and beam loss of the anti-correlated painting in the beam commissioning are somewhat different. Through the machine studies, we have carefully analyzed these differences and studied their reasons.

physics.acc-ph↗

arXiv2019

Residual orbit of BC bump for CSNS/RCS

In a beam cycle, there is a chicane bump (BC bump) in the injection region of China Spallation Neutron Source (CSNS). It is a core part of the injection system and the important guarantee that the Linac beam injecting into the rapid cycling synchrotron (RCS). During the beam commissioning, the residual orbit of BC bump, i.e. the closedorbit distortion (COD) due to the imperfect BC bump, was an important problem which can affect the orbit correction and beam loss control of the RCS. In this paper, a method to measure the residual orbit of BC bump was studied and given. By using the three auxiliary powers of BC magnets, a method to correct the residual orbit of BC bump was developed. The numerical simulation results showed that the measurement and correction methods had worked well and they can be applied to the beam commissioning of CSNS/RCS. The measurement results in the machine study showed that the residual orbit of BC bump is not large and can be corrected by the three auxiliary powers of BC magnets.

physics.acc-ph↗

arXiv2018

Injection orbit matching for CSNS/RCS

The Rapid Cycling Synchrotron(RCS) of China Spallation Neutron Source(CSNS) employs painting injection to achieve uniform beam distribution and suppress space-charge effects. In the painting injection, the mismatch between the injection beam orbit and circulating orbit could make the non-uniformity of beam distribution and emittance growth, which may lead to beam loss. To match the injection beam orbit and the circulating beam orbit, it is necessary to identify the orbit of injection beam relative to the circulating orbit in the injection point. However, it's hard to measure this relative injection orbit directly. Theoretically, the relative injection beam orbit can be deduced by measuring the turn-by-turn beam position of a single turn injection beam. However, the intensity of single turn injected beam is too low to be measured with sufficient signal-noise ratio by using beam position monitor(BPM). In this paper, two effective methods based on multi-turn injection and turn-by-turn BPM are given to perform the match between the injection and the circulating beam orbit. The simulation results and application in the beam commissioning of CSNS/RCS show the validity of the methods.

physics.acc-ph↗

arXiv2017

Study of the Magnetizing Relationship of the Kickers for CSNS

The extraction system of CSNS mainly consists of two kinds of magnets: eight kickers and one lambertson magnet. In this paper, firstly, the magnetic test results of the eight kickers were introduced and then the filed uniformity and magnetizing relationship of the kickers were given. Secondly, during the beam commissioning in the future, in order to obtain more accurate magnetizing relationship, a new method to measure the magnetizing coefficients of the kickers by the real extraction beam was given and the data analysis would also be processed.

physics.acc-ph↗

arXiv2016

Study on the magnetic measurement results of the injection system for CSNS/RCS

A combination of the H- stripping and phase space painting method is used to accumulate a high intensity beam in the Rapid Cycling Synchrotron (RCS) of the China Spallation Neutron Source (CSNS). The injection system for CSNS/RCS consists of three kinds of magnets: four direct current magnets (BC1-BC4), eight alternating current magnets (BH1-BH4 and BV1-BV4), two septum magnets (ISEP1 and ISEP2). In this paper, the magnetic measurements of the injection system were introduced and the data analysis was processed. The field uniformity and magnetizing curves of these magnets were given, and then the magnetizing fitting equations were obtained.

physics.acc-ph↗

arXiv2016

Detection of supernova neutrinos at spallation neutron sources

After considering the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein effects, the neutrino collective effects, and the Earth matter effects, the detection of supernova neutrinos at China Spallation Neutron Sources is studied and the event numbers of different flavor supernova neutrinos observed through various reaction channels are calculated with the neutrino energy spectra described by the Fermi-Dirac distribution and "beta fit" distribution respectively. Furthermore, the numerical calculation method of supernova neutrino detection on the Earth is applied to some other spallation neutron sources, and the total event numbers of supernova neutrinos observed through different reactions channels are given.

hep-ph↗

arXiv2016

Study on accelerator neutrino detection at a spallation source

In this paper, we study the detection of accelerator neutrinos produced at the China Spallation Neutron Source (CSNS). Using the code FLUKA, we have simulated the production of neutrinos in the proton beam on the tungsten target and obtained the yield efficiency, numerical flux, and average energy of different flavors of neutrinos. Furthermore, detections of these accelerator neutrinos are investigated in two reaction channels, the neutrino-electron reactions and neutrino-carbon reactions. The event numbers of different flavors of neutrinos have also been calculated.

hep-ph↗

arXiv2015

Electron emission of stripping foil and collimation system for CSNS/RCS

For the Rapid Cycling Synchrotron of the China Spallation Neutron Source (CSNS/RCS), the electron emission plays an important role in the accelerator limitation. The interactions between the proton beam and the stripping foil were studied, and the electron scattering processes were simulated by the ORBIT and FLUKA codes. Then, the electron energy distribution and the electron yielding rate can be given. Furthermore, the interactions between the proton beam and the collimation system were studied, and the electron scattering processes were simulated. Then, the energy distribution of the primary electron emission can be given and the yielding rate of the primary electron can be obtained.

physics.acc-ph↗

arXiv2015

Study on the injection beam commissioning software for CSNS/RCS

The China Spallation Neutron Source (CSNS) accelerator uses H- stripping and phase space painting method of filling large ring acceptance with the linac beam of small emittance. The beam commissioning software system is the key part of CSNS accelerator. The injection beam commissioning software for CSNS contains three parts currently: painting curve control, injection beam control and injection orbit correction. The injection beam control contains two subsections: single bunch beam calculation and LRBT beam control at the foil. The injection orbit correction also contains two subsections: injection orbit correction by the calculation and injection trim power control.

physics.acc-ph↗

arXiv2015

Study on the transverse painting during the injection process for CSNS/RCS

For the China Spallation Neutron Source (CSNS), a combination of the H- stripping and phase space painting method is used to accumulate a high intensity beam in the Rapid Cycling Synchrotron (RCS). In this paper, firstly, the injection processes with different painting ranges and different painting methods were studied. With the codes ORBIT and MATLAB, the particle distribution and painting image were obtained. Then, the reasonable painting range which is suitable for the aperture size and magnet gap can be selected. Since the real field uniformity of BH3 and BV3 is not completely in conformity with the design requirement, the painting method and painting range also need to be selected to reduce the effects of bad field uniformity.

physics.acc-ph↗

arXiv2013

Detection of supernova neutrinos on the Earth for large theta13

Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the recent experimental result about the large mixing angle $θ_{13}$ ($\backsimeq8.8^{\circ}$) provided by the Daya Bay Collaboration and applying the available knowledge for the neutrino conversion probability in the high resonance of SN, $P_{H}$, which is in the form of hypergeometric function in the case of large $θ_{13}$, we deduce the expression of $P_{H}$ taking into account the shock wave effects. It is found that $P_{H}$ is not zero in a certain range of time due to the shock wave effects. After considering all the four physical effects and scanning relevant parameters, we calculate the event numbers of SN neutrinos detected at the Daya Bay experiment. From the numerical results, it is found that the behaviors of neutrino event numbers detected on the Earth depend on the neutrino mass hierarchy and neutrino spectrum parameters including the temperature $T_α$, the dimensionless pinching parameter $η_α$ or $β_α$ (where $α$ refers to neutrino flavor), the average energy $< E_α>$, and the SN neutrino luminosities $L_α$. We also compare the results of two parametrization methods for the neutrino energy distributions and give the ranges of SN neutrino event numbers that will be detected at the Daya Bay experiment.

hep-ph↗

arXiv2012

Beam losses due to the foil scattering for CSNS/RCS

For the Rapid Cycling Synchrotron of China Spallation Neutron Source (CSNS/RCS), the stripping foil scattering generates the beam halo and gives rise to additional beam losses during the injection process. The interaction between the proton beam and the stripping foil was discussed and the foil scattering was studied. A simple model and the realistic situation of the foil scattering were considered. By using the codes ORBIT and FLUKA, the multi-turn phase space painting injection process with the stripping foil scattering for CSNS/RCS was simulated and the beam losses due to the foil scattering were obtained.

physics.acc-ph↗

arXiv2012

Study on the injection optimization and transverse coupling for CSNS/RCS

The injection system of the China Spallation Neutron Source uses H- stripping and phase space painting method to fill large ring acceptance with the linac beam of small emittance. The emittance evolution, beam losses, and collimation efficiency during the injection procedures for different injection parameters, such as the injection emittances, starting injection time, twiss parameters and momentum spread, were studied, and then the optimized injection parameters was obtained. In addition, the phase space painting scheme which also affect the emittance evolution and beam losses were simulated and the optimization range of phase space painting were obtained. There will be wobble in the power supply of the injection bumps, and the wobble effects were presented. In order to study the transverse coupling, the injection procedures for different betatron tunes and momentum spreads were studied.

physics.acc-ph↗

arXiv2012

The effects of injection beam parameters and foil scattering for CSNS/RCS

The China Spallation Neutron Source (CSNS) uses H- stripping and phase space painting method to fill large ring acceptance with the linac beam of small emittance. The dependence of the painting beam on the injection beam parameters was studied for the Rapid Cycling Synchrotron (RCS) of CSNS. The injection processes for different momentum spread, rms emittance of the injection beam, injection beam matching were simulated, then the beam losses, 99% and rms emittances were obtained and the optimized ranges of injection beam parameters were given. The interaction between the H- beam and the stripping foil was studied and the foil scattering was simulated. Then, the stripping efficiency was calculated and the suitable thickness of the stripping foil was obtained. The energy deposition on the foil and the beam losses due to the foil scattering were also studied.

physics.acc-ph↗

arXiv2010

Acquire information about neutrino parameters by detecting supernova neutrinos

We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle $θ_{13}$, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about $θ_{13}$ and neutrino masses by detecting supernova neutrinos. We apply these methods to some current neutrino experiments.

astro-ph.HE↗

arXiv2009

Supernova Neutrinos Detection On Earth

In this paper, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about $θ_{13}$ smaller than $1.5^\circ$ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.

hep-ph↗

arXiv2009

Realistic Earth matter effects and a method to acquire information about small θ_{13} in the detection of supernova neutrinos

In this paper, we first calculate the realistic Earth matter effects in the detection of type II supernova neutrinos at the Daya Bay reactor neutrino experiment which is currently under construction. It is found that the Earth matter effects depend on the neutrino incident angle $θ$, the neutrino mass hierarchy $Δm_{31}^{2}$, the crossing probability at the high resonance region inside the supernova, $P_{H}$, the neutrino temperature, $T_α$, and the pinching parameter in the neutrino spectrum, $η_α$. We also take into account the collective effects due to neutrino-neutrino interactions inside the supernova. With the expression for the dependence of $P_H$ on the neutrino mixing angle $θ_{13}$, we obtain the relations between $θ_{13}$ and the event numbers for various reaction channels of supernova neutrinos. Using these relations, we propose a possible method to acquire information about $θ_{13}$ smaller than $1.5^\circ$. Such a sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment which has a sensitivity of the order of $θ_{13}\sim 3^\circ$. Furthermore, we apply this method to other neutrino experiments, i.e. Super-K, SNO, KamLAND, LVD, MinBooNE, Borexino, and Double-Chooz. We also study the energy spectra of the differential event numbers, ${\rm d}N/{\rm d}E$.

hep-ph↗