Please try to evaluate the articles from my library, which I collected on this issue. The ideas of these papers are clear.

Try Wilmar Schaufeli's Utrecht Work Engagement Scale. It has a long and short verision in several languages:

http://www.wilmarschaufeli.nl/downloads/test-manuals-2/

Thank you both for your resources and incite. I am aware of the absorption, dedication, and vigor conceptualization of engagement (UWES). The models I am testing have very clear emotional and cognitive pathways, which obvious lends itself to the emotional, physical, and cognitive conceptualization of engagement (aka the North American version). The problem is that in ESM and diary studies, all I find are various forms of the UWES.

What about the FEVS items? Are public domain. Can send along if you don't yet have them.

I have access to the items. My only concern is that this 'Alternative FEVS Engagement Scale' is relatively new. I will consider it and will definitely talk to my team about it. Thank you, Nancy.

UWES-9 item (De Bruin & Henn)

http://www.amsciepub.com/doi/abs/10.2466/01.03.PR0.112.3.788-799

Just to add the following for your reading list:

https://lirias.kuleuven.be/bitstream/123456789/486835/1/32.pdf

http://www.beanmanaged.com/doc/pdf/arnoldbakker/articles/articles_arnold_bakker_164.pdf

http://www.ibam.com/pubs/jbam/articles/vol10/No1/JBAM_10_1_3.pdf

https://www.researchgate.net/publication/232478318_Defining_and_measuring_work_engagement_Bringing_clarity_to_the_concept

http://www.ijhpm.com/pdf_2940_a993c02c925736a05cdeb3a19dda011a.html

Article Defining and measuring work engagement: Bringing clarity to ...

You can use this insttrument in this article...

Dear Daniele,

Work engagement is one of those often talked-about, but rarely understood concepts. The attached (which has simplified reflections too) may be useful for you. 

Opatha

For that, one must read Katz and Kahn (1978) book.

Maybe Shirom-Melamed Vigor Measure  might be an option?

http://www.shirom.org/arie/index.html