Hi Radoslaw, So, I have a document that I’m fairly certain was supplied by JEOL that says: Johansson crystals: TAPH, PETHS, LIFHS, PETL Johan crystals: TAPJ, PETJ, LIF, LIFL, LIFH, PETH + Multilayers and STE That doesn’t answer your question – I had always assumed like Ron, that the ‘J’ simply stood for JEOL. But, they are in any case ‘normal’ crytals – We had TAPJs on our old 8600. Best wishes, Stuart ____________________________ Stuart Kearns School of Earth Sciences University of Bristol, UK Tel. +44 (0)117 331 5004/5012 [log in to unmask]<mailto:[log in to unmask]> From: JEOL-Focused Probe Users List <[log in to unmask]> on behalf of Allaz Julien <[log in to unmask]> Reply to: JEOL-Focused Probe Users List <[log in to unmask]> Date: Wednesday, 23 September 2020 at 09:43 To: "[log in to unmask]" <[log in to unmask]> Subject: Re: [PROBEUSERS] TAPJ, TAPH, TAPL or TAP? Hi Radoslaw, Unless I am mistaking, historically the “J” indicate that the monochromator geometry is of “Johansson” type (in opposite to Johann). The Johansson geometry has the 2d lattice bent at a radius of 2R, and the monochromator is then further grinded to a R radius, offering thus a perfect focusing of the X-ray on the detector. Nowadays it is common to still see it on the PET monochromator (PETJ) but I haven’t seen it on other monochromator… Best, Julien ########################### Dr. Julien Allaz Head assistant for SEM/EPMA Inst. für Geochemie und Petrologie ETH Zürich NW E 84 Clausiusstrasse 25 8092 Zürich Switzerland Tel: +41 44 632 37 20 Fax: +41 44 632 16 36 Email: [log in to unmask]<mailto:[log in to unmask]> ########################### On 23 Sep 2020, at 10:10, Michallik Radoslaw (GTK) <[log in to unmask]<mailto:[log in to unmask]>> wrote: Hi, I’ve been working on an old JEOL JXA 8600 with the normal “small size” x-tals i.e. TAP. I know that large crystals are i.e. TAPL (normal spectrometer 140mm) and high intensity crystals are TAPH for the H-Type spectrometer with a smaller Rowland circle (100mm). But what are i.e. TAPJ x-tals? What does the “J” stands for? I’ve noticed that they are usually mounted with a gas-flow proportional counter. I just started recently at my new work place and we’ll have a configuration with TAPJ and PETJ crystals on our new FE-EPMA from JEOL. Thank you in advance for your help. Kind regards, Radoslaw Michallik Researcher Circular Economy Solutions Geological Survey of Finland GTK Vuorimiehentie 2K, FI-02151 Espoo, Finland Tel. +358 29 503 0345, +358 50 340 9701 [log in to unmask]<mailto:[log in to unmask]> www.gtk.fi<http://www.gtk.fi/> I @GTK.fi<https://twitter.com/GTK_FI> The Geological Survey of Finland provides solutions for more sustainable growth. For Earth and for Us. <image001.png> **** JEOL Probe Users Listserver Moderator: Anette von der Handt, [log in to unmask]<mailto:[log in to unmask]>, Electron Microprobe Lab, University of Minnesota Post a message: send your message to [log in to unmask]<mailto:[log in to unmask]> Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask]<mailto:[log in to unmask]> On-line help and FAQ: http://probelab.geo.umn.edu/jeoluserlist.html * **** JEOL Probe Users Listserver Moderator: Anette von der Handt, [log in to unmask]<mailto:[log in to unmask]>, Electron Microprobe Lab, University of Minnesota Post a message: send your message to [log in to unmask]<mailto:[log in to unmask]> Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask]<mailto:[log in to unmask]> On-line help and FAQ: http://probelab.geo.umn.edu/jeoluserlist.html * **** JEOL Probe Users Listserver Moderator: Anette von der Handt, [log in to unmask], Electron Microprobe Lab, University of Minnesota Post a message: send your message to [log in to unmask] Unsubscribe: send "SIGNOFF PROBEUSERS" to [log in to unmask] On-line help and FAQ: http://probelab.geo.umn.edu/jeoluserlist.html *