Design of hadronic calorimeter for DarkSHINE experiment

The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.

Research on in-situ condition preserved coring and testing systems

As shallow resources are increasingly depleted,the mechanics'theory and testing technology of deep insitu rock has become urgent.Traditional coring technologies obtain rock samples without retaining the in-situ environmental conditions,leading to distortion of the measured parameters.Herein,a coring and testing systems retaining in-situ geological conditions is presented:the coring system that obtains in-situ rock samples,and the transfer and testing system that stores and analyzes the rocks under a reconstructed environment.The ICP-Coring system mainly consists of the pressure controller,active insulated core reactor and insulation layer and sealing film.The ultimate bearing strength of 100 MPa for pressurepreservation,temperature control accuracy of 0.97%for temperature-retained are realized.CH_(4)and CO permeability of the optimized sealing film are as low as 3.85 and 0.33 ppm/min.The average tensile elongation of the film is 152.4%and the light transmittance is reduced to 0%.Additionally,the pressure and steady-state temperature accuracy for reconstructing the in-situ environment of transfer and storage system up to 1%and±0.2 is achieved.The error recorded of the noncontact sensor ring made of lowdensity polymer is less than 6%than that of the contact test.The system can provide technical support for the deep in-situ rock mechanics research,improving deep resource acquisition capabilities and further clarifying deep-earth processes.

Deep original information preservation by applying in-situ film formation technology during coring

Accurately obtaining the original information of an in-situ rock via coring is a significant guiding step for exploring and developing deep oil and gas resources.It is difficult for traditional coring technology and equipment to preserve the original information in deep rocks.This study develops a technology for insitu substance-preserved(ISP),moisture-preserved(IMP),and light-preserved(ILP)coring.This technology stores the original information in real time by forming a solid sealing film on the in-situ sample during coring.This study designed the ISP-IMP-ILP-Coring process and tool.In addition,an ISP-IMP-ILPCoring process simulation system was developed.The effects of temperature,pressure,and film thickness on the quality of the in-situ film were investigated by performing in-situ film-forming simulation experiments.A solid sealing film with a thickness of 2-3 mm can be formed;it completely covers the core sample and has uniform thickness.The film maintains good ISP-IMP-ILP properties and can protect the core sample in the in-situ environment steadily.This study verifies the feasibility of“film formation during coring”technology and provides strong support for the engineering application of ISP-IMP-ILPCoring technology.

Hollow glass microspheres/silicone rubber composite materials toward materials for high performance deep in-situ temperaturepreserved coring

Deep petroleum resources are stored under high temperature and pressure conditions,with the temperature having a significant influence on the properties of rocks.Deep in-situ temperature-preserved coring(ITP-coring)devices were developed to assess deep petroleum reserves accurately.Herein,hollow glass microspheres(HGMs)/silicone rubber(SR)composites that exhibit excellent thermal insulation properties were prepared as thermal insulation materials for deep ITP-coring devices.The mechanism and process of heat transfer in the composites were explored,as well as their other properties.The results show that the HGMs exhibit good compatibility with the SR matrix.When the volume fraction of the HGMs is increased to 50%,the density of the HGMs/SR composites is reduced from 0.97 to 0.56 g/cm^(3).The HGMs filler introduces large voids into the composites,reducing their thermal conductivity to 0.11 W/m·K.The addition of HGMs into the composites further enhances the thermal stability of the SR,wherein the higher the HGMs filler content,the better the thermal stability of the composites.HGMs significantly enhance the mechanical strength of the SR.HGMs increase the compressive strength of the composites by 828%and the tensile strength by 164%.Overall,HGMs improve the thermal insulation,pressure resistance,and thermal stability of HGMs/SR composites.

Tuberous sclerosis complex-lymphangioleiomyomatosis involving several visceral organs:A case report

BACKGROUND Lymphangioleiomyomatosis(LAM)is a rare cystic lung disease characterized by the proliferation,metastasis,and infiltration of smooth muscle cells in the lung and other tissues,which can be associated with tuberous sclerosis complex(TSC).The disorder of TSC has a variable expression,and there is great phenotypic variability.CASE SUMMARY A 32-year-old Chinese woman with a history of multiple renal angioleiomyolipoma presented with a productive cough persisting for over 2 wk.Highresolution chest computed tomography revealed interstitial changes,multiple pulmonary bullae,bilateral pulmonary nodules,and multiple fat density areas of the inferior mediastinum.Conventional and contrast ultrasonography revealed multiple high echogenic masses of the liver,kidneys,retroperitoneum,and inferior mediastinum.These masses were diagnosed as angiomyolipomas.Pathology through thoracoscopic lung biopsy confirmed LAM.Furthermore,high-throughput genome sequencing of peripheral blood DNA confirmed the presence of a heterozygous mutation,c.1831C>T(p.Arg611Trp),of the TSC2 gene.The patient was diagnosed with TSC-LAM.CONCLUSION We highlight a rare case of TSC-LAM and the first report of a mediastinum lymphangioleiomyoma associated with TSC-LAM.

Right-heart contrast echocardiography reveals missed patent ductus arteriosus in a postpartum woman with pulmonary embolism: A case report

BACKGROUND As an established,simple,inexpensive,and surprisingly effective diagnostic tool,right-heart contrast echocardiography(RHCE)might help in solving a vexing diagnostic problem.If performed appropriately and interpreted logically,RHCE allows for differentiation of various usual and unusual right-to-left shunts based on the site of injection and the sequence of microbubble appearance in the heart.CASE SUMMARY A 31-year-old woman was readmitted to hospital with a 2-mo history of worsening palpitation and chest distress.Two years prior,she had been diagnosed with postpartum pulmonary embolism by conventional echocardiography and computed tomography angiography.While the latter showed no sign of pulmonary artery embolism,the former showed pulmonary artery hypertension,moderate insufficiency,and mild stenosis of the aortic valve.RHCE showed microbubbles appearing in the left ventricle,slightly delayed after rightheart filling with microbubbles;no microbubbles appeared in the left atrium and microbubbles’appearance in the descending aorta occurred nearly simultaneous to right pulmonary artery filling with microbubbles.Conventional echocardiography was re-performed,and an arterial horizontal bidirectional shunt was found according to Doppler enhancement effects caused by microbubbles.The original computed tomography angiography findings were reviewed and found to show a patent ductus arteriosus.CONCLUSION RHCE shows a special imaging sequence for unexplained pulmonary artery hypertension with aortic valve insufficiency and simultaneous patent ductus arteriosus.

Pseudomonas aeruginosa-related effusive-constrictive pericarditis diagnosed with echocardiography:A case report

BACKGROUND Effusive-constrictive pericarditis(ECP)is an uncommon pericardial syndrome.Careful echocardiographic examination may provide helpful information not only for diagnosing but also for managing ECP.ECP has various etiologies;however,Pseudomonas aeruginosa(P.aeruginosa)infection has not been reported as a cause to date.Herein,we present a rare case of ECP caused by P.aeruginosa infection,which was followed up using echocardiography.CASE SUMMARY A 30-year-old man was admitted to our hospital with a 2-mo history of cough,dyspnea,bloating,palpitations,and lower-extremity edema.The patient was initially diagnosed with pericardial effusion by transthoracic echocardiography.Drainage of pericardial effusion was performed to relieve the clinical symptoms.A follow-up echocardiogram showed that the pericardial effusion had decreased;however,the right atrial pressure continued to increase,and signs of constrictive pericarditis were observed upon a more comprehensive inspection.Therefore,the diagnosis of ECP was established based on the comprehensive pre-and postpericardiocentesis echocardiographic findings.An urgent pericardectomy was subsequently performed,which significantly relieved the patient's clinical symptoms,and the signs of pericardial constriction on echocardiography improved.Pericardial effusion and pericardial culture showed growth of P.aeruginosa.CONCLUSION ECP induced by P.aeruginosa infection remains a rare disease.The presence of echocardiographic features of constrictive pericarditis after pericardiocentesis therapy is highly indicative of ECP.

Prospective study of light dark matter search with a newly proposed DarkSHINE experiment

Dark photons have been well motivated as strong candidates for dark force carriers and light dark matter in the sub-GeV mass range.Compared with collider experiments,fixed-target experiments provide a complementary approach to searching for dark photons,particularly in the lower mass range.We have studied the physics potential of the electron-on-target experiment based on the Shanghai SHINE facility,which provides 10 MHz single electron beam at 8 GeV energy.This analysis focuses on dark photons being produced via electron and nucleon interaction and then decays to dark matter candidates,which escape detection as missing momentum in the detector.This experiment takes advantage of using missing momentum to enhance signal versus background separation power.In this study,signal samples as a function of dark photon mass and an inclusive background sample with 2.5 billion events are simulated with GEANT4.For better background estimates,major rare background processes have also been simulated.This paper presents the experiment and detector design,signal and background simulations,analysis strategy,and the prospective study of the experiment sensitivity.With 9×10^(14) electron-on-target events(about three years running),this experiment is expected to rule out most of the sensitive regions predicted by popular dark photon models.