The clinical trials of tumor therapy using heavy ions beam 12C are now in progress at Institute of Modern Physics in Lanzhou. In order to achieve the precise radiotherapy with the high energy 12C beam in active pencil...The clinical trials of tumor therapy using heavy ions beam 12C are now in progress at Institute of Modern Physics in Lanzhou. In order to achieve the precise radiotherapy with the high energy 12C beam in active pencil beam scanning mode, we have developed an ionization chamber(IC) as an online monitor for beam intensity and also a dosimeter after calibration. Through the choosing of working gas and voltage, optimizing of the electrics and the read-out system, calibrating the linearity, the detector system provide us one of the simple and highly reliable way to monitoring the beam during the active pencil beam scanning treatments. The measurement results of this detector system show that it could work well under the condition of high energy 12C beam in active pencil beam scanning mode.展开更多
In this paper we present a timing detector which has low detection threshold and is radiation-resistant.The photons induced by radioactive beam ions passing through a thin plastic-scintillator foil BC422,emit from the...In this paper we present a timing detector which has low detection threshold and is radiation-resistant.The photons induced by radioactive beam ions passing through a thin plastic-scintillator foil BC422,emit from the foil center corresponding to one focal point of an aluminum ellipsoidal mirror and are reflected to another focus point at which the cathode of a photomultiplier tube locates.A time resolution of about 115 ps can be achieved for1 2N of 58.5 MeV/u and 130 ps for1 7B of 43.7 MeV/u.The counting rate up to 10 8packets per second(pps) is allowed.展开更多
Laser cooling is the most promising method to achieve high phase-space densities, even crystalline beams for relativistic heavy ion at storage rings[1]. A test laser cooling experiment has been performed with 12C3+ io...Laser cooling is the most promising method to achieve high phase-space densities, even crystalline beams for relativistic heavy ion at storage rings[1]. A test laser cooling experiment has been performed with 12C3+ ions at the CSRe. In this experiment, the 12C3+ ions were produced from an electron cyclotron resonance (ECR) ion source, and due to the residual gas and the injection gases such as CO and CO2, 16O4+ ions will be produced at the same time.展开更多
Mass is one of the fundamental properties of atomic nuclei. Isochronous mass spectrometry (IMS), using astorage ring combined with an in-flight separator, has been shown to be a powerful tool for mass measurementof ex...Mass is one of the fundamental properties of atomic nuclei. Isochronous mass spectrometry (IMS), using astorage ring combined with an in-flight separator, has been shown to be a powerful tool for mass measurementof exotic nuclei[1]. Recently, masses of many proton-rich nuclides were accurately determined at the HIRFL-CSRfacility[2]. In this paper, we described the first isochronous mass measurement of neutron-rich nuclides at CSRe.This experiment was performed at the end of 2011. In the experiment, the primary beam of 86Kr28+ ions wasaccumulated and accelerated to an energy of 460.65 MeV/u in the synchrotron CSRm. The 86Kr28+ ions were fastextracted and focused on a 15 mm thick beryllium target which was placed at the entrance of the RIBLL2 (anin-flight fragment separator).展开更多
Laser cooling is one of the most promising techniques to reach high phase-space densities and achieve phasetransition, ordered beam even crystalline beam for relativistic heavy ion beams at storage rings[1]. In order ...Laser cooling is one of the most promising techniques to reach high phase-space densities and achieve phasetransition, ordered beam even crystalline beam for relativistic heavy ion beams at storage rings[1]. In order torealize laser cooling at the CSRe in IMP, we performed a test experiment by using a pulsed laser system to coolthe relativistic 12C3+ ion beams on the CSRe in September 2014. Fig. 1 is the schematic view of the experimentalsetup.展开更多
In conventional isochronous mass spectrometry (IMS), single time-of-flight (TOF) method is adopted to measurethe ions' revolution times in a storage ring which can then be used to calculate the ions' masses. H...In conventional isochronous mass spectrometry (IMS), single time-of-flight (TOF) method is adopted to measurethe ions' revolution times in a storage ring which can then be used to calculate the ions' masses. However, themass-to-charge ratio (m=q) is only related to the revolution time (T) under the condition that is equal to taccording to the following equation:展开更多
Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly r...Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly reducesthe influence of the velocity difference on the ion revolution periods, the revolution period difference ΔT =T ??TRof a stored ion with respect to a reference time TR is directly related to its mass-to-charge ratio difference Δ(m=q),written in the first order as:展开更多
基金Supported by the National Nature Science Foundation of China (No. 10305015, No.10475098)the Major Program of the Chinese Academy of Science (No. O701050YZD)
文摘The clinical trials of tumor therapy using heavy ions beam 12C are now in progress at Institute of Modern Physics in Lanzhou. In order to achieve the precise radiotherapy with the high energy 12C beam in active pencil beam scanning mode, we have developed an ionization chamber(IC) as an online monitor for beam intensity and also a dosimeter after calibration. Through the choosing of working gas and voltage, optimizing of the electrics and the read-out system, calibrating the linearity, the detector system provide us one of the simple and highly reliable way to monitoring the beam during the active pencil beam scanning treatments. The measurement results of this detector system show that it could work well under the condition of high energy 12C beam in active pencil beam scanning mode.
基金Supported by National Nature Science Foundation of China (No.10205019,10475098)Doctoral Foundation of Southwest University (No.SWNUB2005028)Hundred Talent Project of CAS (0501080BR0)
文摘In this paper we present a timing detector which has low detection threshold and is radiation-resistant.The photons induced by radioactive beam ions passing through a thin plastic-scintillator foil BC422,emit from the foil center corresponding to one focal point of an aluminum ellipsoidal mirror and are reflected to another focus point at which the cathode of a photomultiplier tube locates.A time resolution of about 115 ps can be achieved for1 2N of 58.5 MeV/u and 130 ps for1 7B of 43.7 MeV/u.The counting rate up to 10 8packets per second(pps) is allowed.
基金National Natural Science Foundation of China(11504388), West Light Doctoral Foundation of Chinese Academy of Sciences
文摘Laser cooling is the most promising method to achieve high phase-space densities, even crystalline beams for relativistic heavy ion at storage rings[1]. A test laser cooling experiment has been performed with 12C3+ ions at the CSRe. In this experiment, the 12C3+ ions were produced from an electron cyclotron resonance (ECR) ion source, and due to the residual gas and the injection gases such as CO and CO2, 16O4+ ions will be produced at the same time.
文摘Mass is one of the fundamental properties of atomic nuclei. Isochronous mass spectrometry (IMS), using astorage ring combined with an in-flight separator, has been shown to be a powerful tool for mass measurementof exotic nuclei[1]. Recently, masses of many proton-rich nuclides were accurately determined at the HIRFL-CSRfacility[2]. In this paper, we described the first isochronous mass measurement of neutron-rich nuclides at CSRe.This experiment was performed at the end of 2011. In the experiment, the primary beam of 86Kr28+ ions wasaccumulated and accelerated to an energy of 460.65 MeV/u in the synchrotron CSRm. The 86Kr28+ ions were fastextracted and focused on a 15 mm thick beryllium target which was placed at the entrance of the RIBLL2 (anin-flight fragment separator).
文摘Laser cooling is one of the most promising techniques to reach high phase-space densities and achieve phasetransition, ordered beam even crystalline beam for relativistic heavy ion beams at storage rings[1]. In order torealize laser cooling at the CSRe in IMP, we performed a test experiment by using a pulsed laser system to coolthe relativistic 12C3+ ion beams on the CSRe in September 2014. Fig. 1 is the schematic view of the experimentalsetup.
文摘In conventional isochronous mass spectrometry (IMS), single time-of-flight (TOF) method is adopted to measurethe ions' revolution times in a storage ring which can then be used to calculate the ions' masses. However, themass-to-charge ratio (m=q) is only related to the revolution time (T) under the condition that is equal to taccording to the following equation:
文摘Isochronous mass spectrometry in storage rings is a successful technique for the precision mass measurements ofthe nuclides with half-lives down to tens of microseconds[1]. Since the isochronous condition =t greatly reducesthe influence of the velocity difference on the ion revolution periods, the revolution period difference ΔT =T ??TRof a stored ion with respect to a reference time TR is directly related to its mass-to-charge ratio difference Δ(m=q),written in the first order as:
